Upload
others
View
2
Download
0
Embed Size (px)
Citation preview
Tore Nilssen – Strategic Competition – Theme 1 – Slide 1
Strategic competition American term: Industrial organization A better name: The economics of industry
- the study of activities within an industry, mainly with respect to competition among the firms in a product market.
Why is this topic important? The model of perfect competition is unrealistic.
- Who set the prices? – The firms.
- Can they influence the price? – Yes, for example if their products differ, or if they are few.
But: difficult to find a general model of imperfect competition. Many models with varying applications
- Is it smart to have a whole battery of models?
The predictions from the perfect-competition model do
not fit. In many industries: - high profits - p > MC
Competition policy
Tore Nilssen – Strategic Competition – Theme 1 – Slide 2
The study of an industry - few firms - partial equilibrium - how do the firms compete with each other?
- setting prices? quantities? - making investments? advertising? R&D?
capacity? - location of outlets
- what do they do to avoid competition?
- product differentiation - entry deterrence - predatory actions - collusion - merger
Various models, all with the same analytical tool: game theory
Tore Nilssen – Strategic Competition – Theme 1 – Slide 3
What is the right model to use? - What kind of market are we looking at?
Example: market for petrol vs. market for cars petrol: homogeneous good car: heterogeneous good petrol: easy for firms to supervise each other’s prices car: price supervision difficult Product differentiation weaker competition petrol market more competitive Price supervision: easy to coordinate on prices petrol market less competitive Both markets may have the same mark-up, but explanations may differ. In order to understand how firms in an industry compete (or not), we need a catalogue of different models.
Tore Nilssen – Strategic Competition – Theme 1 – Slide 4
Even in the study of a single industry, it may be helpful to have different models of strategic competition in mind. Example: Norwegian airlines.
(source: Norwegian Competition Authority)
Predation Entry deterrence Non-price competition Collusion Merger Consumer switching costs
Tore Nilssen – Strategic Competition – Theme 1 – Slide 5
Central concepts from game theory Extensive form vs. normal form Strategy vs. action Pure strategy vs. mixed strategy Dominated strategy Nash equilibrium Subgame-perfect equilibrium Repeated games Repetition of game theory: Tirole, secs 11.1-11.3 (for ch 9: secs 11.4-11.5) Exercises 11.1, 11.4, 11.9.
Tore Nilssen – Strategic Competition – Theme 1 – Slide 6
Competition in the short run or: Static oligopoly theory Firms make decisions simultaneously Actions chosen from continuous action spaces Differentiable profit functions First-order conditions Nash equilibrium with 2 firms:
0, *
2*1
i
i
s
ss i = 1, 2
Each firm’s decision is optimum, given the other firm’s equilibrium decision. The other firm’s decision is exogenous. Thus, we can find one firm’s optimum decision given the other firm’s choice: Best-response functions R1(s2) is firm 1’s best-response function, defined by:
0
,
1
2211
s
ssR
Tore Nilssen – Strategic Competition – Theme 1 – Slide 7
Best-response curves: The slope of the best-response curve:
02
21
12
121
12
ds
ssdR
s
21
1221
12
2
121
'
s
ss
ds
dRsR
Second-order condition 021
12
s
Therefore: sign R1’(s2) = sign 21
12
ss
s2*
R2(s1)
R1(s2)
s1
s2
s1*
Tore Nilssen – Strategic Competition – Theme 1 – Slide 8
021
12
ss
:
An increase in s2 implies a reduction in firm 1’s payoff from a marginal increase in s1. This implies a reduction in firm 1’s optimum. The two firms’ choice variables are strategic substitutes.
021
12
ss
:
An increase in s2 implies an increase in firm 1’s payoff from a marginal increase in s1. This implies an increase in firm 1’s optimum. The two firms’ choice variables are strategic complements. Generally, but not always: prices are strategic complements quantities are strategic substitutes
Tore Nilssen – Strategic Competition – Theme 1 – Slide 9
Price competition A firm’s price is a short-term commitment. So a regular picture of competition in the short run is one of competition in prices. Modelling is a trade-off between making a model
- simple, so that we can understand it; and
- reasonable, so that we can use it. Let us start out with simplicity. Two firms, homogeneous goods (perfect substitutes). Consumers care only about price. Market demand: D(p), D’ < 0. Constant unit cost: c. No capacity constraints. Firms choose prices simultaneously and independently. Equilibrium prices – Bertrand equilibrium. (Joseph Bertrand, 1883) Firm 1’s profit: 1(p1, p2) = (p1 – c)D1(p1, p2), where
21
2112
1
211
211
if ,0
if,
if ,
,
pp
pppD
pppD
ppD
Tore Nilssen – Strategic Competition – Theme 1 – Slide 10
1(p1, p2) is discontinuous, because D1(p1, p2) is. First-order approach not applicable. Nash equilibrium: 1(p1*, p2*) 1(p1, p2*), p1. 2(p1*, p2*) 2(p1*, p2), p2. Result: There exists a unique equilibrium, in which p1* = p2* = c Two steps in the proof. Step 1: This is an equilibrium. Step 2: No other price combination is an equilibrium. [Exercise 5.1: cost asymmetry]
p1
p2
(i)
(ii)
(iv)
(iii)
c
Tore Nilssen – Strategic Competition – Theme 1 – Slide 11
The same result holds for any number of firms 2. So there is nothing between monopoly and perfect competition (the Chicago school). Or is there? The model lacks realism.
Resolving the Bertrand paradox (i) Product differentiation Consumers care for both price and product characteristics. No longer true that R(c) = c. If p2 = c, then p1 = c + provides firm 1 with positive profit. Thus, p = c no longer equilibrium. [Theme 3] (ii) Time horizon Consider the case p1 = p2 > c. Not an equilibrium, because firm 1 is better off with reducing its price strictly below p2. But what if firm 2 can respond to this? Would it set a price even lower? If so, could it be that firm 1 does not have incentives for a price reduction to start with? [Theme 2]
Tore Nilssen – Strategic Competition – Theme 1 – Slide 12
(iii) Capacity constraints Firms cannot sell more than they are able to produce. Capacity constraints: 1q and 2q . Suppose 1q < D(c). p = c is no longer equilibrium Suppose firm 1’s price is p1 = c. If now firm 2 sets p2 = c + , then firm 1 faces a higher demand than its capacity. Some consumers will have to go to the high-price firm 2, who therefore earns a profit. Capacity constraints are an extreme version of decreasing returns to scale. [Next slides]
Tore Nilssen – Strategic Competition – Theme 1 – Slide 13
Price competition with capacity constraints Consumers are rationed at the low-price firm. But who are the rationed ones? As before: two firms; homogeneous goods.
Efficient rationing If p1 < p2 and 1q < D(p1), then the residual demand facing firm 2 is:
otherwise ,0
,if,~ 121222
qpDqpDpD
This is the rationing that maximizes consumer surplus: The consumers with the highest willingness to pay get the low price.
D(p)
q2
p2
p1
1
q
Tore Nilssen – Strategic Competition – Theme 1 – Slide 14
Proportional rationing Let p1 < p2 and 1q < D(p1). Instead of favouring the consumers with the highest willingness to pay, all consumers have the same chance of getting the low price. Probability of being supplied by the low-price firm 1 is:
1
1
pD
q
The residual demand facing the high-price firm 2 is:
1
1222 1
~
pD
qpDpD
Not efficient – some consumers get supplies despite having a willingness to pay below p2, consumers’ marginal cost.
q2
D(p) p2
p1
1
q
Tore Nilssen – Strategic Competition – Theme 1 – Slide 15
Example Two firms, homogeneous demand: D(p) = 1 – p Zero marginal costs of production: c = 0. High investment costs have led to low capacity:
3
121 qq .
Assume efficient rationing. Define: p* = 1 – 21 qq . [Note: p* ≥
3
1 > c.]
Is p1 = p2 = p* an equilibrium? Note that D(p*) = 21 qq ; total capacity exactly covers demand at this price. Can another price be preferable for firm 1 to p*, if firm 2 sets p2 = p*? (i) Consider p1 < p2 = p*. A lower price for firm 1
without any increase in sales. (ii) Consider p1 > p2 = p*. Firm 1’s sales less than
before: q1 = 11
~pD = D(p1) – 2q = 1 – p1 – 2q
p1 = 1 – q1 – 2q
Tore Nilssen – Strategic Competition – Theme 1 – Slide 16
Profit of firm 1: 1 = p1 11
~pD
Equivalently: 1 = (1 – q1 – 2q )q1 Is it profitable for firm 1 with a price above p*? Equivalently: Is it profitable with a quantity below 1q ?
211
1 21 qqdq
d
Second-order condition: 21
12
dq
d < 0.
021| 211
111
qqdq
dqq
Optimum is at 1q . Thus, the optimum price for firm 1 is p*. Equivalently for firm 2. Thus, p1 = p2 = p* in equilibrium. Is this equilibrium unique? Yes. Larger capacities: No equilibria in pure strategies. [Exercise 5.2]
Tore Nilssen – Strategic Competition – Theme 1 – Slide 17
Capacity a more long-term decision than price Consider the following two-stage game: Stage 1: Firms choose capacities Stage 2: Firms choose prices Investment costs: c0 per unit of capacity Suppose c0 is so high that, in equilibrium, capacities will be low. We can then make use of our analysis of the price game: Prices equal p*. Profit net of investment costs: 1( 1q , 2q ) = {[1 – ( 1q + 2q )] – c0} 1q . Now, the game is equivalent to a one-stage game in capacities where demand = total capacity = total supply. That is, a one-stage game in quantities. (Augustin Cournot, 1838) With efficient rationing and a concave demand function, the two games are equivalent in equilibrium outcome, for all c0. Therefore, a model of one-stage quantity competition, with prices coming from nowhere, can be understood as a simple substitute for a more realistic but more complex model where firms compete in capacities and thereafter in prices.
Tore Nilssen – Strategic Competition – Theme 1 – Slide 18
The Cournot model Two firms choose quantities simultaneously. Costs: Ci(qi) Total production: Q = q1 + q2
Inverse demand: P(Q), P’ < 0. Profit, firm 1: 1(q1, q2) = q1P(q1 + q2) – C1(q1). First-order condition:
1
1
q = P(q1 + q2) + q1P’(q1 + q2) – C1’(q1) = 0
q1P’(q1 + q2) – the infra-marginal effect of an
increase in quantity
Equilibrium: 1
1
q = 0;
2
2
q = 0.
Tore Nilssen – Strategic Competition – Theme 1 – Slide 19
For firm 1:
P – C1’ = – q1P’ =
QP
Q
q
QPQ
q1
'
1
11 '
Q
P
P
Q
q
P
CP
'
1
11'
L1 = P
CP '1 – the Lerner index of firm 1
1 = Q
q1 – firm 1’s market share
D(p) – the market demand
D(P(Q)) Q
D’(p) P’(Q) = 1 Demand elasticity:
Q
P
PD
PD'
1'
L1 = 1
Note: (i) 1/ > 0 L1 > 0 P > C1’. (ii) Monopoly: 1 = 1, and L1 = 1/.
Tore Nilssen – Strategic Competition – Theme 1 – Slide 20
n firms: n
i iqQ1
i(q1, …, qn) = qiP(Q) – Ci(qi)
0''
1
ii
ii
i
Cdq
dQPqQP
q
Example: P(Q) = a – Q;
Ci(qi) = C(qi) = cqi, where a > c. First-order condition firm i: a – Q – qi – c = 0. All firms identical q1 = … = qn = q, Q = nq Applied to the first-order condition: a – nq – q – c = 0
1
n
caq
P = a – nq = cn
cacn
nca
n
cana
111
Q = nq = can
n 1
= 2
111
n
caq
n
cacqn
cacq
n P c, Q a – c, 0. [Exercises 5.3, 5.4, 5.5]
Tore Nilssen – Strategic Competition – Theme 1 – Slide 21
Bertrand vs. Cournot Competing models? – No. Firms set prices. When capacity constraints are of little importance, the Bertrand model is the preferred one. When capacity constraints are present to an important extent (decreasing returns to scale), the Cournot model is the best choice. Measuring concentration A substitute for measuring price-cost margins, since costs are unobservable. A popular measure: the Herfindahl index. n
i iHR1
2
Model: n firms, Ci(qi) = ciqi, quantity competition Total industry profits:
i Hi iiii
ii ii RD
DPQqPqcP
'
22
Assume: = 1 pD(p) = k D(p) = k/p D2/(– D’) = k Hi i Rk
The Herfindahl index is proportional to total industry profits. [Exercises 5.6, 5.7]
Tore Nilssen – Strategic Competition – Theme 2 – Slide 1
Dynamic oligopoly theory
• Dynamic price competition • Collusion
Collusion – price coordination Illegal in most countries
- Explicit collusion not feasible - Legal exemptions
Recent EU cases
• Banking – approx. 1.7 billion Euros in fines (2013) • Cathodic ray tubes – 1.5 billion Euros (2012) • Gas – approx. 1.1 billion Euros in fines (2009) • Car glass – approx. 1.4 billion Euros (2008)
Website: ec.europa.eu/competition/cartels/cases/cases.html Puerto Rico, US, 2013: 5-year sentence for price-fixing
Tore Nilssen – Strategic Competition – Theme 2 – Slide 2
Tacit collusion
Hard to detect – not many cases. Repeated interaction Theory of repeated games Deviation from an agreement to set high prices has
- a short-term gain: increased profit today - a long-term loss: deviation by the others later on
Tacit collusion occurs when long-term loss > short-term gain Model Two firms, homogeneous good, C(q) = cq Prices in period t: (p1t, p2t) Profits in period t: π1(p1t, p2t), π2(p1t, p2t) History at time t: Ht = (p10, p20, …, p1, t – 1, p2, t – 1) A firm’s strategy is a rule that assigns a price to every possible history.
Tore Nilssen – Strategic Competition – Theme 2 – Slide 3
A subgame-perfect equilibrium is a pair of strategies that are in equilibrium after every possible history: Given one firm’s strategy, for each possible history, the other firm’s strategy maximizes the net present value of profits from then on. T – number of periods T finite: a unique equilibrium period T: p1T = p2T = c, irrespective of HT. period T – 1: the same and so on T infinite (or indefinite) At period τ, firm i maximizes
( )∑∞
=
−
τ
τπδt
ttit pp 21 , ,
r+=
11δ
The best response to (c, …) is (c, …). But do we have other equilibria? Can p > c be sustained in equilibrium?
Tore Nilssen – Strategic Competition – Theme 2 – Slide 4
Trigger strategies: If a firm deviates in period t, then both firms set p = c from period t + 1 until infinity. [Optimal punishment schemes? Renegotiation-proofness?] Monopoly price: pm = arg max (p – c)D(p) Monopoly profit: πm = (pm – c)D(pm) A trigger strategy for firm 1: • Set p10 = pm in period 0 • In the periods thereafter,
� p1t(Ht) = pm, if Ht = (pm, pm, …, pm, pm) � p1t(Ht) = c, otherwise
If a firm collaborates, it sets p = pm and earns πm/2 in every period. The optimum deviation: pm – ε, yielding ≈ πm for one period. An equilibrium in trigger strategies exists if:
2
mπ(1 + δ + δ2 + … ) ≥ πm + 0 + 0 + …
⇔ δ−1
121
≥ 1 ⇔ δ ≥ 21
Tore Nilssen – Strategic Competition – Theme 2 – Slide 5
The same argument applies to collusion on any price p ∈ (c, pm]. ⇒ Infinitely many equilibria. The Folk Theorem. Collusion when demand varies Demand stochastic. Periodic demand is
low: D1(p) with probability ½ high: D2(p) with probability ½ D1(p) < D2(p), ∀ p.
The demand shocks are i.i.d. Each firm sets its price after having observed demand. What are the best collusive strategies for the two firms? Trigger strategies: A deviation is followed by p = c forever.
π2
π1
Tore Nilssen – Strategic Competition – Theme 2 – Slide 6
What are the best collusive prices? One price in low-demand periods and one in high-demand periods: p1 and p2. πs(p) – total industry profit in state s when both firms set p. With prices p1 and p2 in the two states, each firm’s expected net present value is:
( )( ) ( )( )∑∞=
−+−= 0 222
111
221
221
tt cp
pDcp
pDV δ
= ( )δ−141 [D1(p1)(p1 – c) + D2(p2)(p2 – c)]
= ( ) ( )
( )δππ
−+
142211 pp
The best possible collusive price in state s is:
psm = arg max (p – c)Ds(p), s = 1, 2.
πs
m = (psm – c)Ds(ps
m), s = 1, 2. If the firms can collude on these prices, then:
( )1 2
4 1
m m
Vπ π
δ+=−
Tore Nilssen – Strategic Competition – Theme 2 – Slide 7
A deviation in state s receives a gain equal to: πsm
For (p1m, p2
m) to be equilibrium prices, we must have: πs
m ≤ ½πsm + δV ⇔ πs
m ≤ 2δV The difficulty is state 2 (high-demand), since π1
m < π2m.
The equilibrium condition becomes:
( )1 2
2 24 1
m mm π ππ δ
δ+≤−
⇔ 0
2
13
2 δδ
ππ
≡+
≥
m
m
0 < m
m
2
1
ππ
< 1 ⇒ 2
1 < δ0 < 3
2
But what if δ ∈ [
2
1 , δ0)? Can we still find prices at which
the firms can collude?
Tore Nilssen – Strategic Competition – Theme 2 – Slide 8
The problem is again state 2. We need to set p2 so that
( ) ( )( )
1 2 22 2 2
4 1
m pp
π ππ δ
δ+
≤−
⇒ ( ) mp 122 32π
δδπ−
=
2
1 ≤ δ < 3
2 ⇒ δ
δ32−
≥ 1 ⇒ π2 ≥ π1
So: prices below monopoly price in high-demand state – during boom. Could even be that p2 < p1. But is this a price war? More realistic demand conditions: Autocorrelation – business cycle. Collusion most difficult to sustain just as the downturn starts. Haltiwanger & Harrington, RAND J Econ 1991 Kandori, Rev Econ Stud 1991 Bagwell & Staiger, RAND J Econ 1997
[Exercise 6.4]
Tore Nilssen – Strategic Competition – Theme 2 – Slide 9
Empirical studies of collusion • the railroad cartel
- Porter Bell J Econ 1983 - Ellison RAND J Econ 1994
• collusion among petrol stations
- Slade Rev Econ Stud 1992 • collusion in the soft-drink market: prices and advertising
- Gasmi, et al., J Econ & Manag Strat 1992 • collusion in procurement auctions
- Porter & Zona J Pol Econ 1993 (road construction) - Pesendorfer Rev Econ Stud 2000 (school milk)
Infrequent interaction Suppose the period length doubles.
δ → δ2 Collusion feasible if:
δ2 ≥ 21
⇔ 2
1≥δ ≈ 0.71
Tore Nilssen – Strategic Competition – Theme 2 – Slide 10
Multimarket contact Market A: Frequent interaction, period length 1. Collusion if δ ≥ ½. Market B: Infrequent interaction, period length 2. Collusion if δ2 ≥ ½. (How could frequency vary across markets?) What if both firms operate in both markets? Can the firms obtain collusion in both markets even in cases where δ2 < ½ < δ? A deviation is most profitable when both markets are open. Deviation yields: 2πm Collusion yields: [πm/2] every period, plus [πm/2] every second period (starting today) Collusion can be sustained if:
2
mπ[1 + δ + δ2 + … ] +
2
mπ[1 + δ2 + δ4 + … ] ≥ 2πm
⇔ 21
121
11
21
2 ≥−
+− δδ
⇔ 4δ2 + δ – 2 ≥ 0 ⇔ 8
133−≥δ ≈ 0.59
Tore Nilssen – Strategic Competition – Theme 2 – Slide 11
Secret price cuts, or: Price coordination when supervising the partners is difficult
Own demand observable Market demand not observable Other firms’ prices not observable When own demand is low, is it because market demand is low, or because partners default? Punishment (p = c) is necessary. But punishment forever? Can firms coordinate prices without being able to observe each other’s prices? Punishment starts when one observes low demand. Punishment phase lasts for a finite number of periods. Even colluding firms have periods of ‘‘price wars”. Model: Two firms; homogeneous products; MC = c. In each period: firms set prices; consumers choose the firm with the lower price. Market demand is either: D = 0, with probability α; D = D(p), with probability (1 – α).
Tore Nilssen – Strategic Competition – Theme 2 – Slide 12
Both firms know it if at least one firm has zero profit in a period. Either:
- market demand is zero and both firms have zero profit, or
- one firm has cut its price and knows that the other firm has zero profit
Strategy: • Start with p = pm. • Set p = pm until (at least) one firm has zero profit. • If this happens, then set p = c for T periods. • After T periods, return to p = pm until (at least) one firm
has zero profit.
And so on. Is there an equilibrium in which each firm plays this strategy? T must be determined.
Tore Nilssen – Strategic Competition – Theme 2 – Slide 13
Two phases: • Colluding phase • Punishment phase
V+ = net present value of a firm in the colluding phase V− = net present value of a firm at the start of the punishment phase
( ) −++ +
+−= VVV
m
αδδπα2
1
V− = δTV+ Equilibrium condition: V+ ≥ (1 − α)(πm + δV−) + αδV− = (1 − α)πm + δV−
( ) ( ) −−+ +−≥+
+−⇔ VVV m
m
δπααδδπα 12
1
( )2
m
VVπδ ≥−⇔ −+
( )2
1m
TVπδδ ≥−⇔ +
Tore Nilssen – Strategic Competition – Theme 2 – Slide 14
( ) ++++ +
+−= VVV T
m1
21 αδδπα
( )( ) 111
21
++
−−−
−= T
m
Vαδδα
πα
( )( ) ( )
21
112
1
1
mT
T
m
πδδαδδα
πα≥−
−−−
−+
2δ(1 − α) + (2α − 1)δT + 1 ≥ 1 The best equilibrium has the highest possible V+. The firms’ problem: maxT V
+, such that: 2δ(1 − α) + (2α − 1)δT + 1 ≥ 1 But: dV+/dT < 0. So we restate the problem. min T, such that: 2δ(1 − α) + (2α − 1)δT + 1 ≥ 1
Tore Nilssen – Strategic Competition – Theme 2 – Slide 15
T = 0 is too low – there has to be some punishment, even under collusion: 2δ(1 − α) + (2α − 1)δ = δ < 1 And the lefthand side must be increasing in T:
( ) ( )[ ]11212 +−+− T
dT
d δααδ
( )� 2
10ln12
0
1 <⇔>−=<
+ αδδα T
If α ≥ ½, then collusion is impossible: The probability of zero market demand is too large. If α < ½, then 2α − 1 < 0. But (2α − 1)δT + 1 → 0 as T → ∞.
Equilibrium condition satisfied for some T if also 2δ(1 − α) ≥ 1
All in all: Collusion can occur in equilibrium if:
• α < ½
• α
δ−
≥1
121
T is chosen as the lowest integer that satisfies:
2δ(1 − α) + (2α − 1)δT + 1 ≥ 1 Example: δ = ¾, α = ¼. Condition: (¾)T + 1 ≤ ¼ ⇒ T* = 4. But often T* is smaller: δ = 0.9, α = 0.2 ⇒ T* = 2.
Tore Nilssen – Strategic Competition – Theme 2 – Slide 16
Price rigidities • Menu costs • Price reactions not punishments, but attempts to regain
market share Suppose
- a price is fixed for two periods - firms alternate at setting price
Duopoly with alternating price setting • A discrete price grid • Markov strategies: strategies based only on directly
payoff-relevant information Example: A trigger strategy is not Markov; no price from the past has a direct effect on a firm’s profit today, only an indirect effect, because other firms use trigger strategies. A restriction to Markov strategies would be too strong when moves are simultaneous. Here, moves are alternating. Model: duopoly; each firm’s price fixed for two periods; firm 1 sets price in odd-numbered periods (1 – 3 – 5 – …), firm 2 in even-numbered periods (2 – 4 – 6 – …).
Tore Nilssen – Strategic Competition – Theme 2 – Slide 17
Markov reaction functions: Let pit be the price set by firm i in period t. Firm 1’s reaction function:
p1, 2k + 1 = R1(p2, 2k), k = 0, 1, 2, … Firm 2’s reaction function:
p2, 2k + 2 = R2(p1, 2k + 1), k = 0, 1, 2, …
Markov perfect equilibrium: An equilibrium in Markov reaction functions. At the start of each subgame, the firm that makes the move chooses an optimum strategy, given the restriction only to pay attention to payoff-relevant information, and given the other firm’s equilibrium strategy. The two firms at any point in time:
‘‘the active” and ‘‘the other” Consider the active firm’s decision today. Suppose the other firm set the price ph last period; this is also its price today. – We are in state h. Vh – the active firm’s net present value in state h. Wh – the other firm’s net present value in state h. Tomorrow, the roles are changed.
Tore Nilssen – Strategic Competition – Theme 2 – Slide 18
Profit per period: π(own price, the other’s price) ⇒ ( )[ ]khk
kh WppV δπ += ,max
A symmetric equilibrium: R1(⋅) = R2(⋅) = R(⋅) Mixed strategy: A firm may be indifferent between one or more prices, and in equilibrium, the other firm has beliefs about which of these prices will be chosen. These beliefs will then constitute the firm’s mixed strategy. αhk – the probability (according to the other firm’s beliefs) that a firm in state h chooses price pk.
Note: 1=∑k
hkα
A symmetric equilibrium can be described by a transition matrix: Suppose there are H possible prices.
��� ���� ��
1
111
state to
......
..
..
..
......
state from
k
h
HHH
H
αα
αα
= A
Tore Nilssen – Strategic Competition – Theme 2 – Slide 19
Equilibrium conditions
( )[ ]∑ +=k
khkhkh WppV δπα ,
( )[ ]∑ +=l
llkklk VppW δπα ,
These are the values of Vh and Wk that follow from the transition matrix A.
[Vh – π(pk, ph) – δWk]αhk = 0, ∀ h, k. Vh ≥ π(pk, ph) + δWk, ∀ h, k.
Complementary slackness: If αhk > 0, it must be because Vh = π(pk, pl) + δWk, that is, because pk maximizes the firm’s net present value in state h.
1=∑
khkα , ∀ h
αhk ≥ 0, ∀ h, k.
Tore Nilssen – Strategic Competition – Theme 2 – Slide 20
Example: D(p) = 1 – p; c = 0 The price grid: ph =
6
h , h = 0, …, 6.
Competitive price: p0 = 0. Monopoly price: pm = p3 = ½. Two (symmetric Markov perfect) equilibria (at least):
1. ‘‘Kinked demand curve”: The other firm does not follow you if you increase the price but undercuts you if you decrease the price.
R(1) = R(6
5 ) = R(3
2 ) = R(2
1 ) = R(0) = 2
1 ;
R(3
1 ) = 6
1 ; R(6
1 ) ∈ {6
1 , 2
1 }.
• Either the game starts in state 3 and stays there, or it
ends there sooner or later (absorbing state).
• A mixed strategy in state 1 – a waiting game (‘‘war of attrition”): Each firm is indifferent between meeting p1 with p1, and making a short-term sacrifice in order to get the monopoly price from next period on.
• The equilibrium is sustainable only if each firm is able
to supply the whole market demand at p1 = 6
1 : D(6
1 ) =
6
5 . In the absorbing state 3, each firm sells 2
1 D(p3) = 4
1
but needs to keep an excess capacity of 6
5 – 4
1 = 12
7 .
Tore Nilssen – Strategic Competition – Theme 2 – Slide 21
2. Price war: The firms undercut each other.
R(1) = R(6
5 ) = 3
2 ; R(3
2 ) = 2
1 ; R(2
1 ) = 3
1 ;
R(3
1 ) = 6
1 ; R(6
1 ) = 0; R(0) ∈ {0, 6
5 }.
• Unstable prices: no absorbing state.
• Edgeworth cycle.
• Again a waiting game. But now the price jumps
beyond the monopoly price. • Multiple equilibria, even when we restrict attention to
Markov strategies. • Fewer equilibria than in an ordinary repeated game. • p = c is no longer an equilibrium; there is always some
price collusion in equilibrium. Other cases of dynamic price competition • Brand loyalty / consumer switching costs
• Durable goods
Tore Nilssen – Strategic Competition – Theme 3 – Slide 1
Product differentiation How far does a market extend? Which firms compete with each other? What is an industry? Products are not homogeneous. Exceptions: petrol, electricity. But some products are more equal to each other than to other products in the economy. These products constitute an industry. A market with product differentiation. But: where do we draw the line? Example:
- beer vs. soda? - soda vs. milk? - beer vs. milk?
Tore Nilssen – Strategic Competition – Theme 3 – Slide 2
Two kinds of product differentiation (i) Horizontal differentiation: Consumers differ in their
preferences over the product’s characteristics. Examples: colour, taste, location of outlet.
(ii) Vertical differentiation: Products differ in some
characteristic in which all consumers agree what is best. Call this characteristic quality. (quality competition)
Horizontal differentiation Two questions: 1. Is the product variation too large in equilibrium? 2. Are there too many variants in equilibrium? Question 1: A fixed number of firms. Which product variants will they choose? Question 2: Variation is maximal. How many firms will enter the market? The two questions call for different models.
Tore Nilssen – Strategic Competition – Theme 3 – Slide 3
Variation in equilibrium Will products supplied in an unregulated market be too similar or too different, relative to social optimum? Hotelling (1929) Product space: the line segment [0, 1]. Two firms: one at 0, one at 1. Consumers are uniformly distributed along [0, 1]. A consumer at x prefers product variant x. Consumers have unit demand: p s 1 q
x 0 1
Tore Nilssen – Strategic Competition – Theme 3 – Slide 4
Disutility from consuming product variant y: t(|y – x|) – ‘‘transportation costs”
Linear transportation costs: t(d) = td Generalised prices (with firm 1 at 0 and firm 2 at 1):
p1 + tx and p2 + t(1 – x) The indifferent consumer: xɶ s – p1 – t xɶ = s – p2 – t(1 – xɶ ).
( ) 2 11 2
1,
2 2
p px p p
t
−⇒ = +ɶ
[But check that: (i) 0 ≤ xɶ ≤ 1; (ii) xɶ wants to buy.]
x
s – p1– tx
s – p2 – t(1 – x)
( )1 2,x p pɶ
Tore Nilssen – Strategic Competition – Theme 3 – Slide 5
Normalizing the number of consumers: N = 1 (thousand)
D1(p1, p2) = xɶ = t
pp
221 12 −+
D2(p1, p2) = 1 – xɶ = t
pp
221 21 −+
Constant unit cost of production: c
( ) ( )
−+−=t
ppcppp
221
, 121211π
Price competition.
Equilibrium conditions: 01
1 =∂∂
p
π; 0
2
2 =∂∂
p
π
FOC[1]:
( )������������
soldunit per gain increasesprice increased
12
sales reducesprice increased
1 221
21
t
pp
tcp
−++
−− = 0
⇒ FOC[1]: 2p1 – p2 = c + t FOC[2]: 2p2 – p1 = c + t ⇒ p1* = p2* = c + t
Tore Nilssen – Strategic Competition – Theme 3 – Slide 6
• The indifferent consumer does want to buy if:
tcs2
3+≥
• Prices are strategic complements:
021
21
12
>=∂∂
∂tpp
π
Best-response function: p1 = ½(p2 + c + t) The degree of product differentiation: t Product differentiation makes firms less aggressive in their pricing.
Tore Nilssen – Strategic Competition – Theme 3 – Slide 7
But are 0 and 1 the firms’ equilibrium product variants? Two-stage game of product differentiation: Stage 1: Firms choose locations on [0, 1]. Stage 2: Firms choose prices. Linear vs. convex transportation costs.
• Convex transportation costs analytically tractable – but economically less meaningful?
Assume quadratic transportation costs. Stage 2: Firms 1 and 2 located at a and 1 – b, a ≥ 0, b ≥ 0, a + b ≤ 1. The indifferent consumer: p1 + t(xɶ – a)2 = p2 + t(1 – b – xɶ )2
( ) ( )2 11
12 2 1
p px a a b
t a b
−= + − − +− −
ɶ
D1(p1, p2) = xɶ , D2(p1, p2) = 1 – xɶ
( ) ( ) ( ) ( )
−−−+−−+−=
bat
ppbaacppp
121
21
, 121211π
Tore Nilssen – Strategic Competition – Theme 3 – Slide 8
Equilibrium conditions: 01
1 =∂∂
p
π; 0
2
2 =∂∂
p
π
FOC[1]: 2p1 – p2 = c + t(1 – a – b)(1 + a – b)
FOC[2]: 2p2 – p1 = c + t(1 – a – b)(1 – a + b) Equilibrium:
( )
−+−−+=3
111ba
batcp
( )
−+−−+=3
112ab
batcp
• Symmetric location: a = b ⇒ p1 = p2 = c + t(1 – 2a) • A firm’s price decreases when the other firm gets closer:
01 <db
dp .
• Stage-2 outcome depends on locations:
p1 = p1(a, b), p2 = p2(a, b) Stage 1: π1(a, b) = [p1(a, b) – c]D1(a, b, p1(a, b), p2(a, b))
Tore Nilssen – Strategic Competition – Theme 3 – Slide 9
( )
∂∂
∂∂+
∂∂
∂∂+
∂∂−+
∂∂=
a
p
p
D
a
p
p
D
a
Dcp
a
pD
da
d 2
2
11
1
111
11
1π
( ) ( )
∂∂
∂∂+
∂∂−+
∂∂
∂∂−+=
=
a
p
p
D
a
Dcp
a
p
p
DcpD 2
2
111
1
0
1
111
��� ���� ��
( )�
��
)(
0 effect;
strategic
0
2
0
2
1
0 effect;direct
11
1
�����
<
<>
>
∂∂
∂∂+
∂∂−=
a
p
p
D
a
Dcp
da
dπ
Moving toward the middle: A positive direct effect vs. a negative strategic effect.
( ) ( )
( ) 21
if ,016
53
1321
1221
2121
≤>−−−−=
−−−+=
−−−+=
∂∂
aba
ba
ba
ab
bat
pp
a
D
( )2322 −=
∂∂
ata
p < 0
( )batp
D
−−=
∂∂
12
1
2
1 > 0
( ) ( ) ( ) 016
13
13
2
16
532
2
11 <−−++−=
−−−+
−−−−=
∂∂
∂∂+
∂∂
ba
ba
ba
a
ba
ba
a
p
p
D
a
D
Equilibrium: a* = b* = 0.
Tore Nilssen – Strategic Competition – Theme 3 – Slide 10
Strategic effect stronger than direct effect. Maximum differentiation in equilibrium. Social optimum: No quantity effect. Social planner wants to minimize total transportation costs. (Kaldor-Hicks vs. Pareto) In social optimum, the two firms split the market and locate in the middle of each segment: ¼ and ¾. In equilibrium, product variants are too different. • Crucial assumption: convex transportation costs. • Also other equilibria, but they are in mixed strategies.
[Bester et al., ‘‘A Noncooperative Analysis of Hotelling’s Location Game”, Games and Economic Behavior 1996]
• Multiple dimensions of variants: Hotelling was almost
right [Irmen and Thisse, ”Competition in multi-characteristics spaces: Hotelling was almost right”, Journal of Economic Theory 1998]
• Head-to-head competition in shopping malls: Consumers’ shopping costs.
[Klemperer, “Equilibrium Product Lines”, AER 1992]
Have we really solved the problem whether or not the equilibrium provision of product variants has too much or too little differentiation?
Tore Nilssen – Strategic Competition – Theme 3 – Slide 11
Too many variants in equilibrium? A model without location choice. Focus on firms’ entry into the market. The circular city Circumference: 1 Consumers uniformly distributed around the circle. Number of consumers: 1 Linear transportation costs: t(d) = td Unit demand, gross utility = s Entry cost: f Unit cost of production: c Profit of firm i: πi = (pi – c)Di – f, if it enters, 0, otherwise
Tore Nilssen – Strategic Competition – Theme 3 – Slide 12
Two-stage game. Stage 1: Firms decide whether or not to enter. Assume entering firms spread evenly around the circle.
Stage 2: Firms set prices. If n firms enter at stage 1, then they locate a distance 1/n apart. Stage 2: Focus on symmetric equilibrium. If all other firms set price p, what then should firm i do? Each firm competes directly only with two other firms: its neighbours on the circle. At a distance x~ in each direction is an indifferent consumer:
−+=+ xn
tpxtpi~1~
−+= ipn
tp
tx
21~
Demand facing firm i:
Di(pi, p) = 2x~ = t
pp
ni−+1
Tore Nilssen – Strategic Competition – Theme 3 – Slide 13
Firm i’s problem:
( ) ft
pp
ncp i
iipi
−
−+−= 1maxπ
( ) 011 =−−
−+=∂∂
tcp
t
pp
np ii
i
iπ
n
tcppi +=−2
In a symmetric equilibrium, all prices are equal. ⇒ pi = p.
n
tcp +=
Stage 1: How many firms will enter?
Di = n
1
( ) fn
tf
ncpi −=−−= 2
1π
π = 0 ⇒ f
tn =
⇒ p = c + ft
t = c + tf
Tore Nilssen – Strategic Competition – Theme 3 – Slide 14
Condition: Indifferent consumer wants to buy:
n
tps
2+≥ = c + tf
23
⇔ ( )2
94
cst
f −≤
Exercise 7.3: What if transportation costs are quadratic? [Exercise 7.4: What if fixed costs are large?] Social optimum: Balancing transportation and entry costs.
Average transportation cost: t ( x~21
) = n
t
21
2=
n
t
4
The social planner’s problem:
+n
tnf
n 4min
FOC: 04 2 =−n
tf ⇒ n* =
f
t
21
< ne
Too many firms in equilibrium. Private motivation for entry: business stealing Social motivation for entry: saving transportation costs [Exercise: What happens with ne/n* as N (number of consumers) grows?]
Tore Nilssen – Strategic Competition – Theme 3 – Slide 15
Advertising • informative • persuasive Persuasive: shifting consumers’ preferences? Focus on informative advertising. Hotelling model, two firms fixed at 0 and 1, consumers uniformly distributed across [0,1], linear transportation costs td, gross utility s. A consumer is able to buy from a firm if and only if he has received advertising from it. ϕi – fraction of consumers receiving advertising from firm i
Advertising costs: Ai = Ai(ϕi) = 2
2 iaϕ
Potential market for firm 1: ϕ1. Out of these consumers, a fraction (1 – ϕ2) have not received any advertising from firm 2. The rest, a fraction ϕ2 out of ϕ1, know about both firms. Firm 1’s demand:
D1 = ϕ1 ( )
−++−t
pp
221
1 1222 ϕϕ
Tore Nilssen – Strategic Competition – Theme 3 – Slide 16
A simultaneous-move game. Each firm chooses advertising and price. Firm 1’s problem:
( ) ( ) 21
1222111
, 2221
1max11
ϕϕϕϕπϕ
a
t
ppcp
p−
−++−−=
Two FOCs for each firm.
FOC[p1]: ( ) ( ) 0222
11 21
112
221 =−−
−++−t
cpt
pp ϕϕϕϕϕ
FOC[ϕ1]: ( ) ( ) 022
11 1
12221 =−
−++−− ϕϕϕ at
ppcp
⇒ ( )2
21 21
ϕt
tcpp +−+=
( ) ( )
−++−−=t
ppcp
a 221
11 12
2211 ϕϕϕ
Tore Nilssen – Strategic Competition – Theme 3 – Slide 17
Firms are identical ⇒ Symmetric equilibrium
( )ϕt
tcpp +−+=21
⇒
−+= 12ϕ
tcp
( ) ( )
+−−=21
11 ϕϕϕ cpa
−
−=2
1121 ϕϕ
ϕ ta
⇒
t
a21
2
+=ϕ
Condition: 21≥
t
a
⇒ p = c + at2 Condition: s ≥ c + t + at2 (≥ c + 2t)
• 0<∂∂
a
ϕ, 0>
∂∂a
p
Tore Nilssen – Strategic Competition – Theme 3 – Slide 18
Firms’ profit:
( )221
2
t
a
a
+=π
• 0>∂∂
t
π; 0>
∂∂
a
π!
An increase in advertising costs increases firms’ profits. Two effects of an increase in a on profits: A direct, negative effect. An indirect, positive effect: a ↑ → ϕ↓ → p↑ Firms profit collectively from more expensive advertising. Crucial assumption: convex advertising costs. What about the market for advertising? [Kind, Nilssen & Sørgard, Marketing Science 2009]
Tore Nilssen – Strategic Competition – Theme 3 – Slide 19
Social optimum Average transportation costs
among fully informed consumers: t/4. among partially informed consumers: t/2. The social planner’s problem:
( ) 22
22
212
4max ϕϕϕϕ
ϕ
atcs
tcs −
−−−+
−−
( )
( ) tacs
tcs
2
322
2*
−+−−−=ϕ
[Condition: t ≤ 2(s – c)] Special cases: (i)
t
a → 2
1 : ϕe → 1
ϕ* → ( ) tcs
t
−−−
41 < 1
Too much advertising in equilibrium
(ii) t
a → ∞: ϕe → 0
ϕ* → cs
a
−+1
1 > 0
Too little advertising in equilibrium
Tore Nilssen – Strategic Competition – Theme 3 – Slide 20
Vertical product differentiation Quality competition Consumers agree on what is the best product variant. But they differ in their willingness to pay for quality. s – quality θ – measure of a consumer’s taste for quality. If a consumer of type θ buys a product of quality s at price p, her net utility is: U = θs – p F(θ) – cumulative distribution function of consumer type F(θ’ ) – fraction of consumers with type θ ≤ θ’. Unit demand: If θs – p ≥ 0, then a consumer of type θ buys one unit of the good. One firm: At price p, its demand is D(p) = 1 – ( )
s
pF .
Tore Nilssen – Strategic Competition – Theme 3 – Slide 21
Two firms: Suppose s1 < s2, p1 < p2. The indifferent consumer: θ~s1 – p1 = θ~s2 – p2
12
12~ss
pp
−−=θ
Product 2 quality dominates product 1 if:
θ~ < 1
1
p
s ⇔ 2 1
2 1
p p
s s<
Otherwise 2 1
2 1
p p
s s
≥
, demand is:
D1(p1, p2) =
−−
12
12
ss
ppF –
1
1
s
pF
D2(p1, p2) = 1 –
−−
12
12
ss
ppF
Assume:
Consumers uniformly distributed across [θ, θ ]
Consumers sufficiently different: θ > 2θ (avoiding quality dominance in equilibrium)
Firm 2 is the high-quality producer: s2 > s1.
Production costs independent of quality: c
Tore Nilssen – Strategic Competition – Theme 3 – Slide 22
Equilibrium in prices
12
12~ss
pp
−−=θ
Firm 1’s profit: ( )
−
−−−=
1
1
12
1211 ,max
s
p
ss
ppcp θπ
Best response of firm 1:
( )
( )[ ] ( ) ( )( )
−+<
−+≥≥++−−+
++>+
=
122
122211222
1
21222
1
1
if ,
if ,
if ,2
1
sscpc
sscpsscsspc
sscppc
p
s
s
θθθθ
θ
Firm 2’s profit: ( )
−−−−=
12
1222 ss
ppcp θπ
Best response of firm 2:
( )[ ]1212
12 sspcp −++= θ
Tore Nilssen – Strategic Competition – Theme 3 – Slide 23
Equilibrium prices:
( )( )121 231
sscp −−+= θθ
( )( )122 231
sscp −−+= θθ
Condition for the market being covered, 1
1
s
p≥θ :
c ≤ 3
1 [θ(2s1 + s2) – (θ – θ)(s2 – s1)]
p2
c
c p1
BR2(p1)
BR1(p2)
Tore Nilssen – Strategic Competition – Theme 3 – Slide 24
• The high-quality firm sets the higher price:
p2 – p1 = 3
1 (θ + θ)(s2 – s1) > 0
• The high-quality firm has the higher demand:
12
12~ss
pp
−−=θ =
3
1 (θ + θ) < 2
1 (θ + θ)
D1 = θ~– θ = 3
1 (θ – 2θ)
D2 = θ – θ~ = 3
1 (2θ – θ)
• The high-quality firm has the higher profit:
π1(s1, s2) = (p1 – c)D1 = 9
1 (θ – 2θ)2(s2 – s1)
π2(s1, s2) = (p2 – c)D2 = 9
1 (2θ – θ)2(s2 – s1)
• Firms’ profits are increasing in the quality difference Two-stage game Stage 1: Firms choose qualities Stage 2: Firms choose prices Stage 1 – feasible quality range: [s, s]
Assume: c ≤ 3
1 [θ(2s + s) – (θ – θ)(s – s)]
In equilibrium: s1 = s, s2 = s (or the opposite).
Tore Nilssen – Strategic Competition – Theme 3 – Slide 25
• Asymmetric equilibrium • Maximum differentiation What if …
• c > 3
1 [θ(2s + s) – (θ – θ)(s – s)]
- the low-quality firm will choose a quality above s. • θ < 2θ
- only one firm active in the market: p1 = c, D1 = 0, π1 = 0
p2 = c + 2
1 θ (s – s), D2 = 1, π2 = 2
1 θ (s – s)
- natural monopoly: low consumer heterogeneity makes price competition too intense for the low-quality firm
Natural duopoly for a range of consumer heterogeneity “above” θ > 2θ. Vertical differentiation: the number of firms determined by consumer heterogeneity. Horizontal differentiation: the number of firms determined by market size.
Tore Nilssen – Strategic Competition – Theme 4 – Slide 1
Mergers Why merge?
• Reduce competition – increase market power.
• Cost savings – economies of scale and scope.
• But necessary to merge in order to get bigger? o Input factors in total fixed supply.
Why allow mergers?
• Cost savings o Oliver Williamson: the efficiency defense
Williamson’s point: It may not take a huge cost saving to dominate the deadweight loss from a merger.
Tore Nilssen – Strategic Competition – Theme 4 – Slide 2
But note:
• What if the pre-merger price is not competitive?
o Larger cost savings needed to outweigh deadweight loss.
• Production reshuffling: More of the production in the
industry will be made by the low-cost firm – an additional source of cost savings in the industry.
• What is the appropriate welfare standard? � consumer welfare standard � total welfare standard
• What are the long-term effects of the merger?
� R&D, capacity investments, new products, etc. � collusion
Tore Nilssen – Strategic Competition – Theme 4 – Slide 3
Static effects of mergers
• Unilateral effects
• In general, welfare analyses of mergers are complex – even within rather simple models.
• An alternative: a sufficient condition for a merger to be welfare improving
• The Farrell-Shapiro criterion A merger affects
• the merging firms � price � costs
• the non-merging firms � price
• consumers � price
When a merger is proposed, then – presumably – it is profitable for the merging firms. So the competition authority – when looking for a sufficient condition for a welfare-improvement – can limit the analysis to the merger’s effect on
(i) non-merging firms, and (ii) consumers
→ the external effect of a merger Cost savings affect to a large extent only the merging parties. So focusing on the external effect, we do not need to assess vague statements about cost savings from a merger.
Tore Nilssen – Strategic Competition – Theme 4 – Slide 4
If the merger leads to a higher price, then non-merging firms benefit, and consumers suffer. But what is the total external effect? A merger model with Cournot competition X – total output in the industry xi – firm i’s output yi – all other firms’ output: yi= X – xi Firm i’s costs: ci(xi) Inverse demand: p(X) Firm i’s first-order condition:
p(X) + xip’(X) – ci’(xi) = 0. ⇒
p(xi + yi) + xip’(xi + yi) – ci’(xi) = 0 Firm i’s response to a change in other firms’ output – total differentiation wrt xi and yi: ������ = �� = − � + ���"2� + ���" − �" From which we find firm i’s response to a change in total output:
dxi = Ridyi ⇒ dxi(1 + Ri) = Ri(dxi + dyi) = RidX
⇒ ����� = ��1 + �� = ���� + ���"��� �"���� − �′��� = −λ� < 0
Tore Nilssen – Strategic Competition – Theme 4 – Slide 5
Welfare effects of a merger Two sets of firms:
I – insiders O – outsiders
An infinitesimal merger
• dXI – a small exogenous change in industry output Change in welfare from this merger:
�� = ���� − � � + ��� − �′�����∈�
• Changes in output assessed at market price p. • cI – insiders’ total costs • Note: dxi = – λidXI for each outsider firm • From an outsider firm’s FOC: p – ci’ = – xip’(X) • The external effect of the merger: dE = dW – dπI. • The market share of a firm: si = xi/X.
⇒
�� = ����� + ���� − � �� − ���� + ��′���λ�������∈�
�� = �� − ��� = −��������� + ��′���λ�������∈�
�� = �� λ����∈�− �� ������� = �� λ�!��∈�
− !� ��������
Tore Nilssen – Strategic Competition – Theme 4 – Slide 6
Here, p’ < 0 and, typically, dXI < 0. So the external effect of a merger (the accumulation of many infinitesimal mergers) is positive if and only if:
i i Ii O
s sλ∈
>∑ !
→ An upper bound on the merging firms’ joint (pre-merger) market share in order for their merger to improve welfare. Examples 1. A simple model: constant marginal costs, linear demand
ci” = 0, p” = 0 → λi = 1. Before merger: all firms of equal size. The external effect is positive if the set of merging firms is less than half of all firms: I i
i O
s s∈
<∑ ⇔ m < n/2
• But: will such a merger be profitable?
Tore Nilssen – Strategic Competition – Theme 4 – Slide 7
2. A more sophisticated model: merger between “units of capital”. The Perry-Porter model.
Cost function: C(xi, ki) = "#$%&'$. Marginal costs:
()(#$ = "#$'$
Interpretation: k is an input factor that is in total fixed supply within the industry and not available outside the industry (such as “industry knowledge”). The only way for a firm to expand is to acquire k from other firms, such as through a merger. The more k a firm has, the lower are its costs – cost savings from mergers. A merger between two firms with k1 and k2 units of capital creates a firm with k1 + k2 units of capital.
Also assume linear inverse demand: P(X) = a – X. ⇒
ii
i
k
c kλ =
+
FOC for firm i:
p + xip’ – C’(xi) = 0 ⇔ 0i ii
cp x x
k− − = ⇔ i
i
xp
λ= ⇔
i ii
x s
pλ
ε= =
(since ε = – D’p/D = p/X when demand is linear)
Tore Nilssen – Strategic Competition – Theme 4 – Slide 8
The external effect is positive if:
21I i
i O
s sε ∈
< ∑
• The size of the external effect depends on how
concentrated the non-merging part of the industry is! • A merger is more likely to be welfare-enhancing if the
rest of the industry is concentrated. • A merger among small firms leads to the other, big, firms
expanding, which is good. (Production reshuffling) Criticism of the Farrell-Shapiro approach
• The presumption that the merger is privately profitable may not be valid
� Empire building � Tax motivated mergers � Pre-emption (or encouragement) of other
mergers
Tore Nilssen – Strategic Competition – Theme 4 – Slide 9
Coordinated effects of a merger
• A merger’s effect on collusion
• What effect does a merger have in an industry where firms collude? – On balance: unclear.
� The merging firms now earn more and have
reduced incentives to cheat on the collusive agreement after the merger – the merger makes collusion easier.
• But the picture is complicated: merging firms are bigger and often bigger incentives to break out of punishment phases – thus making collusion more difficult.
� The non-merging firms now earn more without
collusion and therefore have increased incentives for breaking out of the collusive agreement after the merger – the merger makes collusion more difficult.
Regulating mergers
• Merger policy
• The welfare standard
Tore Nilssen – Strategic Competition – Theme 4 – Slide 1
Entry How is the market structure determined in an industry? (number of firms, market shares, etc.) • Entry until profit equals zero
- But what with all the positive profits we observe? • Regulations
- But what with deregulations over the last decades? • Technology
- Economies of scale → natural monopoly • Vertical product differentiation
- natural oligopoly • The established (incumbent) firms’ strategic advantage Three strategies when confronted with an entry threat • Blockading entry: “business as usual” • Deterring entry: Established firms act in such a way that
entry is sufficiently unattractive • Accommodating entry
Tore Nilssen – Strategic Competition – Theme 4 – Slide 2
Technology vs. strategic advantages What kind of fixed costs? • Irreversible/Sunk costs: Strategic advantage • Reversible fixed costs: Economies of scale Contestability theory
Main thesis: economies of scale give only a limited advantage for the established firm Suppose costs are: C(q) = cq + f, if q > 0, 0, otherwise (reversible fixed costs)
qc
pc AC
D(p)
Tore Nilssen – Strategic Competition – Theme 4 – Slide 3
The incumbent firm sets price pc and quantity qc. This situation is sustainable in equilibrium because
- any p < pc by another firm yields a loss - any p > pc by the incumbent firm entails entry
What game is played here? • Prices before quantities? • Short-term commitment of capacity; “hit-and-run entry”.
- Short-term commitment means a small strategic advantage.
- If another firm enters, then the incumbent wants to leave as soon as possible.
- In order to prevent such entry, the incumbent may want to set q > qm.
- As the commitment period shrinks to zero, q → qc. [Tirole, pp. 340-341]
Tore Nilssen – Strategic Competition – Theme 4 – Slide 4
The strategic advantage of being incumbent • a simple model • a general analysis of business strategies How to treat an entry threat? A simple model
Two-stage game: Sequential moves. Stage 1: Incumbent (firm 1) chooses capacity. Stage 2: Potential entrant (firm 2) chooses capacity; zero capacity = no entry. Profit functions (gross of any entry costs): π1(K1, K2) = K1(1 – K1 – K2) π2(K1, K2) = K2(1 – K1 – K2) Ki = capacity choice of firm i.
21
2
KK
i
∂∂∂ π
< 0
Tore Nilssen – Strategic Competition – Theme 4 – Slide 5
Case (i): No entry costs (Stackelberg 1934) Accommodated entry
Stage 2: 2
2
K∂∂π
= 1 – K1 – 2K2 = 0
→ K2 = R2(K1) = 2
1 1K−
Stage 1: π1 = K1[1 – K1 – K2] = K1[1 – K1 – 2
1 1K−]
= ( )
21 11 KK −
→ sK1 = 21
; sK2 = R2(21
) = 41
.
π1 = 81
; π2 = 161
.
Comparison: Simultaneous moves – Cournot.
K1 = R1(K2) = 2
1 2K−
K2 = R2(K1) = 2
1 1K−
→ K1 = K2 = 31
; π1 = π2 = 91
.
Tore Nilssen – Strategic Competition – Theme 4 – Slide 6
Case (ii): Entry costs
f = entry costs. Entry cost not relevant for firm 1 – sunk cost. Profit function of firm 2 net of entry costs: π2(K1, K2) = K2(1 – K1 – K2) – f, if K2 > 0; = 0, if K2 = 0. Blockaded entry: K2 = 0. Stage 1: max π1(K1, 0) = K1(1 – K1).
→ mK1 = 21
.
But when is K2 = 0 the best response to K1 = 21
?
Stage 2: K2 = R2(21
) = 41
, or
0. Profit is:
π2 = π2(21
,41
) = 161
– f, or
0.
→ Entry is blockaded if: f ≥ 161
≈ 0.063.
Tore Nilssen – Strategic Competition – Theme 4 – Slide 7
Deterred entry Which stage-1 quantity makes firm 2 indifferent between entry and no entry? bK1
If K1 ≥ bK1 , then firm 2 chooses no entry. Stage 2:
2
maxK
K2(1 – bK1 – K2) – f
→ K2 = 2
1 1bK−
.
→ 2maxπ = [
21 1
bK−]{1 – bK1 – [
21 1
bK−]} – f
2maxπ = 0 → fK b 211 −=
Stage 1:
f ≥ 161
→
bK1 ≤ mK1 , and firm 1 prefers mK1 to bK1 ; blockaded entry.
f < 161
→
By setting K1 = bK1 , firm 1 deters entry and earns: π
1( bK1 , 0) = bK1 [1 – bK1 ]
= ( f21− )[1 – ( f21− )]
= ff 42 −
Tore Nilssen – Strategic Competition – Theme 4 – Slide 8
Alternatively, firm 1 can accommodate entry and earn 81
(Stackelberg). → Entry deterrence better than entry accommodation when:
π1( bK1 , 0) >
81
ff 42 − > 81
⇔ 032
1
2
1 <+− ff
⇔ 32
1
16
1
2
1 <+− ff
⇔ 32
1
4
12
<
−f
[We are interested in the case f < 1/16, that is, f – 1/4 < 0. Taking squares, we
are interested in the absolute value of f - 1/4, that is 1/4 – f . So:
⇔ 24
1
4
1 <− f ⇔
−>2
11
4
1f ]
⇔
−=
−> 22
3
16
1
2
11
16
12
f ≈ 0.0054
Tore Nilssen – Strategic Competition – Theme 4 – Slide 9
→ What the incumbent chooses to do in face of an entry threat depends on the entry costs: (i) Low entry costs imply accommodated entry:
f ∈ [0,
− 22
3
16
1]
K1 = 1/2, K2 = 1/4. (ii) Medium-sized entry costs imply deterred entry:
f ∈ (
− 22
3
16
1, 16
1)
K1 = f21− , K2 = 0. (iii) High entry costs imply blockaded entry:
f ≥ 161
K1 = 1/2, K2 = 0.
Tore Nilssen – Strategic Competition – Theme 4 – Slide 10
How to treat an entry threat? A more general model Two firms:
firm 1 – the incumbent firm 2 – the potential entrant
Stage 1:
Firm 1 chooses K1. Firm 2 decides whether or not to enter.
Stage 2: Either:
(i) firm 1 is a monopolist, or:
(ii) both firms are in the market and choose their stage-2 variables x1 and x2 simultaneously.
Stage-2 equilibrium: {x1(K1), x2(K1)} Comparative statics How is stage-2 equilibrium affected by the incumbent’s stage-1 move K1? Can we apply comparative statics to an equilibrium?
- uniqueness - stability
Tore Nilssen – Strategic Competition – Theme 4 – Slide 11
Stability: dynamic reasoning in a static model If the stage-2 game changes, then also the stage-2 equilibrium changes. But will the model stabilize at the new equilibrium?
( )12 xR
( )�����21
xR
Tore Nilssen – Strategic Competition – Theme 4 – Slide 12
Stability condition: ”R1 crosses R2 from above” or: R1 steeper than R2, as we see them.
( ) ( )*12*
21
''
1xR
xR−>−
⇔ R1’(x2*) R2’(x1*) < 1
122
2221
22
21
1221
12
<∂∂
∂∂∂∂∂
∂∂∂⇔x
xx
x
xx
ππ
ππ
021
22
21
12
22
22
21
12
>∂∂
∂∂∂
∂−∂
∂∂∂⇔
xxxxxx
ππππ
Firms’ stage-2 profits: π1(K1, x1*(K1), x2*(K1)) and π2(K1, x1*(K1), x2*(K1)) What does firm 1 do at stage 1? • If π2(K1, x1*(K1), x2*(K1)) ≤ 0, then firm 1 has made a
choice of K1 at stage 1 that deters entry. • If π2(K1, x1*(K1), x2*(K1)) > 0, then firm 1 has made a
choice of K1 at stage 1 that accommodates entry.
Tore Nilssen – Strategic Competition – Theme 4 – Slide 13
Entry deterrence
In order to deter entry, firm 1 must set K1 such that π2 = 0. What is the effect on π2 of a change in K1? π2 = π2(K1, x1*(K1), x2*(K1))
�1
*2
0
2
2
1
*1
1
2
1
2
1
2
dK
dx
xdK
dx
xKdK
d
=
∂∂+
∂∂+
∂∂= ππππ
� �����
effectstrategic
1
*1
1
2
effectdirect
1
2
1
2
dK
dx
xKdK
d
∂∂+
∂∂= πππ
Stage-1 choices with a direct effect:
- location - advertising - not capacity
Firm 1 wants π2 so low that π2 = 0. • If dπ2/dK1 < 0, then π2 = 0 is obtained by increasing K1,
that is, by being big. The strategy is to look aggressive by being big: the top dog strategy
• If dπ2/dK1 > 0, then π2 = 0 is obtained by reducing K1,
that is, by being small. The strategy is to look aggressive by being small: the lean-and-hungry-look strategy
Tore Nilssen – Strategic Competition – Theme 4 – Slide 14
Entry accommodation The optimum choice for firm 1 at stage 1 is such that firm 2’s profit after entry is positive: π2(K1, x1*(K1), x2*(K1)) > 0 Since entry is inevitable, firm 1 seeks to maximize own profit, given entry by firm 2. π1 = π1(K1, x1*(K1), x2*(K1))
�1
*2
2
1
1
*1
0
1
1
1
1
1
1
dK
dx
xdK
dx
xKdK
d
∂∂+
∂∂+
∂∂=
=
ππππ
� �����
effectstrategic
1
*2
2
1
effectdirect
1
1
1
1
dK
dx
xKdK
d
∂∂+
∂∂= πππ
Suppose 1
1
K∂∂π
= 0: no direct effect
Tore Nilssen – Strategic Competition – Theme 4 – Slide 15
The strategic effect Assume firms’ stage-2 actions are symmetric: one firm’s effect on the other firm’s profit is qualitatively the same for the two firms.
∂∂=
∂∂
1
2
2
1
xsign
xsign
ππ
From the chain rule:
( )1
*1*
121
*1
1
*2
1
*2 '
dK
dxxR
dK
dx
dx
dx
dK
dx ==
⇒
( )�
curve response
-best slope
2
deterrenceentry effect, strategic
1
*1
1
2
ionaccommodatentry effect, strategic
1
*2
2
1
'RsigndK
dx
xsign
dK
dx
xsign ⋅
∂∂=
∂∂
����������
ππ
Tore Nilssen – Strategic Competition – Theme 4 – Slide 16
(i) Stage-2 variables are strategic substitutes: R2’ < 0.
Example: quantity competition at stage 2.
∂∂−=
∂∂
1
*1
1
2
1
*2
2
1
dK
dx
xsign
dK
dx
xsign
ππ
If an increase in K1 reduces π2, then it increases π1. If an increase in K1 increases π2, then it reduces π1. With strategic substitutes, entry accommodation and entry deterrence are the same thing.
It is good for firm 1 to be aggressive at stage 1, also when it accommodates entry. The strategy is, either:
to look aggressive by being big: the top-dog strategy,
or
to look aggressive by being small: the lean-and-hungry-look strategy
Tore Nilssen – Strategic Competition – Theme 4 – Slide 17
(ii) Stage-2 variables are strategic complements: R2’ > 0.
Example: price competition at stage 2.
∂∂=
∂∂
1
*1
1
2
1
*2
2
1
dK
dx
xsign
dK
dx
xsign
ππ
If an increase in K1 reduces π2, then it also reduces π1. If an increase in K1 increases π2, then it also increases π1.
An entry-accommodating incumbent firm now wants to be non-aggressive!
If firm 1 becomes aggressive when K1 is large, then it now wants to keep K1 down in order to look non-aggressive:
the puppy-dog strategy.
If firm 1 becomes aggressive when K1 is small, then it now wants to have a high K1 in order to look non-aggressive:
the fat-cat strategy.
Tore Nilssen – Strategic Competition – Theme 4 – Slide 18
Business strategies
I. Entry deterrence
Incumbent looks aggressive when investment is
big
small
Top Dog
Lean and Hungry Look
II. Entry accommodation
Incumbent looks aggressive when investment is
big
small
strategic
complements
Puppy Dog
Fat Cat
strategic substitutes
Top Dog
Lean and Hungry Look
Tore Nilssen – Strategic Competition – Theme 4 – Slide 19
Applications:
i) Two-stage model: 1) capacities 2) prices
Prices strategic complements.
Large capacity makes a firm aggressive.
→ Puppy dog strategy: Install a rather small capacity in order to soften the ensuing price competition
ii) Location model: 1) location 2) prices
Again: prices are strategic complements
Interpret K1 as closeness to the centre.
→ Puppy dog strategy: Locate far away from the centre in order to soften the ensuing price competition
Tore Nilssen – Strategic Competition – Theme 4 – Slide 20
iii) Puppy-dog entry
Stage 1: Entrant decides capacity and price Stage 2: Incumbent decides price
Incumbent’s options: • monopoly on residual market: π = A + C • undercut and get the whole market: π = B + C
Entrant’s optimum decision: Choose p and Q such that A > B. [Gelman and Salop, ”Judo Economics: Capacity Limitation and Coupon Competition”, Bell Journal of Economics 14 (1983), 315-325]
A Norwegian example: Viking Cement, 1983. [Sørgard, ”A Consumer as an Entrant in the Norwegian Cement Market”, Journal of Industrial Economics, 41 (1993), 191-204]
xM
cM
pM
p2
c2
�
Q
D(p) – Q D(p)
A
C
B
Tore Nilssen – Strategic Competition – Theme 4 – Slide 21
iv) Persuasive advertising Stage 1: Incumbent invests in loyalty-inducing advertising Stage 2: Price competition (if entry) Entry deterrence: look aggressive High investments → Many loyal firm-1 customers in stage 2 → High price by firm 1 ⇒ Lean and Hungry Look: In order to deter entry, the incumbent firm keeps its advertising low in order to keep post-entry prices, and therefore firm 2’s post-entry profit, low. Entry accommodation: look non-aggressive Firm 1 wants to have many loyal customers, so that its incentives to set a low price in stage 2 are weak. ⇒ Fat Cat strategy Example: the Norwegian ice-cream market 1992 NM (Norske Meierier) vs GB. High level of advertising by NM. Not because NM wanted to keep GB out, but because it wanted to keep GB’s prices high (Fat Cat).
Merger Control: COOP’s acquisition of ICA
Guest Lecture at University of Oslo
March 17 2016
Lars Sørgard
The Norwegian Competition Authority
17.03.2016 Sørgard Merger Control University of Oslo 1
The text today
• Briefly about merger control
– Conditions for blocking a merger
– Some examples
• Theory for the price effect of a merger
– Why market shares can be misleading
– The concept ‘closeness of competition’
• Example: COOP’s acquisition of ICA
– Some facts about the case
– How to analyse closeness of competition
17.03.2016 Sørgard Merger Control University of Oslo 2
17.03.2016 Sørgard Merger Control University of Oslo 3
Merger control in Norway
• If over a threshold level, must report M&A to
Konkurransetilsynet (KT)
– 1 MRD jointly and100 MNOK for the smallest in annual turnover
– But Konkurransetilsynet can also block a merger not reported
• Deadlines
– 70 working days to statement of objections (begrunnet varsel)
– Then 15 working days for the parties and KT each before decision
– Appeal to the ministry (from 1.1.17: Independent appeal body))
• If not accepted, two possible outcomes
– Block the merger
– Accept it given remedies (structural vs behavioral remedies)
0
1
2
3
4
5
6
2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015
Forbud Godkjent på vilkår
Rather large # of decisions
• More active enforcement of merger control in
Norway than in most other countries
– Decisions on almost 3 mergers annually 2004-15
Sørgard Merger Control University of Oslo 4
Merger control decision2004-15
17.03.2016
The most recent examples• Three most recent bans:
– June 2014: Norsk Gjenvinning’s acquisiiton of Avfall Sør Bedrift
– March 2013: Retriever and Innholdsutvikling
– Jan 2013: Nor Tekstil and Sentralvaskeriene
• Five mergers accepted with remedies in 2015:
– September 2015: Aleris acquires Teres (private hospital)• Accepted given sales of hospitals in Trondheim and Tromsø
– August 2015: Orkla acquires Cederroth• Accepted given sales of the brand Asan
– July 2015: St1 acquires Shell• Accepted given that St1 sells all its petrol stations
– March 2015: COOP acquires ICA• Accepted given sales of 93 ICA grocery stores
– February 2015: TeliaSonera acquiresTele2• Accepted given that TeliaSonera, among others, signs a roaming agreement with ICE and
sells mobile network and Network Norway to ICE.
17.03.2016 Sørgard Merger Control University of Oslo 5
The condition for an intervention
– ‘.. vil føre til eller forsterke en vesentligbegrensning av konkurransen i strid med lovens formål’
• Two conditions:1. ‘en vesentlig begrensning av konkurransen’2. ‘i strid med lovens formål’
• Condition 1 is (almost) identical to EU• Condition 2 special for Norway
– Norway a total welfare standard, while most countries a consumer welfare standard
– (Stortinget decided last week to shift to a consumer welfare standard)
17.03.2016 Sørgard Merger Control University of Oslo 6
The text today
• Briefly about merger control
– Conditions for blocking a merger
– Some examples
• Theory for the price effect of a merger
– Why market shares can be misleading
– The concept ‘closeness of competition’
• Example: COOP’s acquisition of ICA
– Some facts about the case
– How to analyse closeness of competition
17.03.2016 Sørgard Merger Control University of Oslo 7
Traditional vs new approach
• Common to define relevant market and usemarket shares in the competitive asessment
– Market delineation not a goal, but a mean to understand the toughness of competition
– # of firms and market shares can be a goodproxy for market power in some industries
• New method for markets with differentiatedproducts
– Market shares can over/underestimate marketpower; how close rivals the merging parties are
– Closeness of competition the key issue
17.03.2016 Sørgard Merger Control University of Oslo 8
Ex.: Somerfield case in England
• In 2005 Somerfield acquired 115 Safeway
grocery stores from Morrison
• Local competition, so they analysed the effect
of each acquired store
• Stage I of the analysis (OFT):
– 23 of the acquired stores problematic
– Passed on the case to Competition Commission (CC)
• Stage II of the analysis (CC):
– Further inquires of 56 stores, and asked Somerfield
to sell out14 stores
17.03.2016 Sørgard Merger Control University of Oslo 9
Stage1: Trad. analysis
• Applied isochrone analysis to delineate themarket– Draw a circle around a store, and the size of the
circle determined by driving time
– Counted the # of rivals after the merger
– If three or less rivals after the merger, the mergerwas problematic
• Different rules for different stores– One-stop shopping 10/15 min travel time city/rural
– Smaller stores 5/10 min travel time city/rural
• Found 1 one-stop shopping and 22 smallerstores as problematic
17.03.2016 Sørgard Merger Control University of Oslo 10
Stage 2: Close rivals?• Isochrone analysis fail to take into account:
– Geographic differentiation; 0-1 decision
– Product differentiation; different store types
17.03.2016 Sørgard Merger Control University of Oslo 11
• CC used another
method to
– To detect how close
rivals they are
– Diversion ratio crucial
Closeness of competition and
price changes after merger
• Each firm price according to marginal cost
• Type of cost saving of importance– Savings in fixed costs not relevant
– Change in marg. cost relevant for price setting
• Farrell/Shapiro (2010): Upward Price Pressure (UPP)
• Upward Price Pressure (UPP) after a merger?– Lower marginal cost; Downward price pressure
– Close rivals; Upward price pressure
17.03.2016 Sørgard Merger Control University of Oslo 12
Upward Price Pressure (UPP)?
• Assume Bertrand w/diff. products
• One product each for firm 1 og 2, and joint profits
after the merger is (assuming only change in c1):
• How large reduciton in c1 for P1 not to
change?
17.03.2016 Sørgard Merger Control University of Oslo 13
0P
qcP
P
qcPq
1
20
22
1
1M
111
• Can apply the first order condition for
product 1 before the merger:
1
10
111P
qcPq
2
0
221
M
11 qcPqcP
UPP forts.
• The price of product 1 will not change if:
17.03.2016 Sørgard Merger Control University of Oslo 14
1
1
1
2
0
221
0
1 )(
Pq
Pq
cPcc M
= Fraction of those
leaving 1 that divert
to 2
• D12 = (Negative of ) Diversion from
product 1 to product 2
Cost
reduciton
11
1212
/
/
pq
pqD
UPP cont..
– E1 = reduction in marginal cost for product 1
• Condition for UPP on product 1:
17.03.2016 Sørgard Merger Control University of Oslo 15
1112
1UPP
L
LED
• Rearranging:
12
0
221
0
1 )( DcPcc M
Cost
reduction
Diversion
ratio
Price-cost margin on
product 2
)1(
)2(
How to find (2)
• Define as follows:
17.03.2016 Sørgard Merger Control University of Oslo 16
– E = reduction in mc:
• We can rearrange (1):
Eccc M 011
01
L
LE
p
cp
p
cpp
E
p
cp
p
c
Ecp
cED
1
0
0
0
0
0
0
• Then we have shown how we go
from (1) to (2)
UPP cont.• But the expression will underestimate
UPP
– Higher product 2 price makes it profitable to
increase price on product 1, and vice versa
– Lower mc for product 2 makes it profitable to
increase producct 1 price , and vice versa
• Taking this into account, it is found that
UPP on both products if:
17
L
L1E
D1
D
17.03.2016 Sørgard Merger Control University of Oslo
UPP cont.
• How large UPP (for a given change in marginal cost) determined by two factors:1. How large diversion to the other merging parties’
product?
2. How large price-cost margin on the sale that is recaptured?
• Other concepts that are analogous to UPP:– GUPPI (Gross Upward Pricing Pressure Index)
– IPR (Illustrative Price Rise)
– …
• But for all of them, 1 and 2 above is valid– Must consider 1) diversion ratios and 2) margins
17.03.2016 Sørgard Merger Control University of Oslo 18
UPP for product 1 after merger
• Product 117.03.2016 Sørgard Merger Control University of Oslo 19
• Product 2
• Optimal price ex ante– Loss = Gain for product
1, and sets price P1
• Incentive to set higher price onproduct 1 ex post merger– Will now recapture some of the
sales lost from product 1
• Value of diversion to product 2, when P1 increasesP1
P2
If firm A acquires firm C
• Crucial how large fraction of A’s customers
that has C as their second choice
– We do not have to find the market shares!
17.03.2016 Sørgard Merger Control University of Oslo 20
AC
B D E
The approach – in practice
• Applies a condition similar to one of those wehave shown– Can assume that the price on both products will
increase
– Quite common to consider UPP, given no change in marginal cost (then applying GUPPI)
• Then checking other aspects not captured by this approach– Low barriers to entry?
– How will rivals’ respond?
– Buyer power (partly captured by margin?)
– Repositioning of products ex post merger?
17.03.2016 Sørgard Merger Control University of Oslo 21
How to detect diversion ratios?• Econometric study (revealed preferences)
– Demand estimation is challenging
– Deadlines in merger cases
• Shock analysis– Effect of, say, sales campaigns
• Surveys among customers (stated preferences)– Used a lot in England, and Norway
• Internal documents– US: Counting how often rivals are mentioned
• Churn data– Can see from data where consumers divert
– Used in mobile phone merger in EU/Norway
17.03.2016 Sørgard Merger Control University of Oslo 22
Ex.: Diversion ratios vs market shares
in mobile phone market in Norway
Sørgard Wireless in Europe 22022016 23
Company Market share
Telenor 50 %
TSN 23 %
Tele2 18 %
Others 9 %
• Market shares bad proxy
for small players’ role?
– New, small players pick up
rather large fraction of
switchers
Diversion ratios from churn data:From/to TSN Tele2 Telenor Others
TSN 34 % 56 % 10 %
Tele2 30 % 60 % 10 %
Telenor 35 % 44 % 21 %
Others 21 % 25 % 54 %
The text today
• Briefly about merger control
– Conditions for blocking a merger
– Some examples
• Theory for the price effect of a merger
– Why market shares can be misleading
– The concept ‘closeness of competition’
• Example: COOP’s acquisition of ICA
– Some facts about the case
– How to analyse closeness of competition
17.03.2016 Sørgard Merger Control University of Oslo 24
The transaction
• Coop acquired all the shares in Ica Norge
– 03.10.2014: Agreement
– 05.11.2014: Reported to Konkurransetilsynet
– 04.03.2015: Deadline for 70 days SO
– 12.05.2015: Deadline for final decision
• Konkurransetilsynet accepted it with remedies
– 11.02.2015: Coop offered remedies
– 03.03.2015: A revised offer
– 04.03.2015: Accepted with remedies
• Had to sell out 93 stores
• Not allowed to complete the deal before this was done
17.03.2016 Sørgard Merger Control University of Oslo 25
The parties
COOP:
• 22,9 % nationalmarket share in 2013
• Integrated procure-ment and distribution
• Nation wide
• Lowprice, super-market, local stores and hypermarket
• ICA:
• 10,4 % national marketshare in 2013
• Integrated procure-ment and distribution(agreement with NG, butnot implemented)
• Nation wide
• Lowprice, super-market and localstores
17.03.2016 Sørgard Merger Control University of Oslo 26
The grocery market - Norway• 5 chains with one or more type of stores each
• 4 integrated chains (wholesale and retail)
• Product market: Groceries sold throughgrocery stores, including all types of stores
• Both a national and a local dimension
• They compete along several dimensions– Price
• Max prices are (mainly) set at the national level
• Prices varies between local areas
• Possible to change prices quickly in local markets
– Other dimensions• Service, product range and quality
• These can be changed in each local store
17.03.2016 Sørgard Merger Control University of Oslo 27
Lavpris60 %
Supermarked25 %
Nærbutikker10 %
Hypermarkeder5 %
Sørgard Merger Control University of Oslo 28
Local markets w/national firms
50 % market share nationally
100 % market share locally
50 % market share nationally
50 % market share locally
17.03.2016 Sørgard Merger Control University of Oslo 29
The counterfactual• Must show a causality from the acqusition
to the dampening of competition
• What is the most likely market structure ifno acquisition?
• In most cases: Status quo
– Market condition at the time of the merger
• Case-by-case evaluation
• Konkurransetilsynet in this case:
– Ica stays in the market, but will scale down
– Ica buyer agreement with Coop or Rema 1000
17.03.2016 Sørgard Merger Control University of Oslo 30
17.03.2016 Sørgard Merger Control University of Oslo 31
Changes due to the acquisition
• Retail, nationally:– # 3 acquires one of the two smallest
– A change from four to three chains
– Inceased symmetry (collusion?)
• Wholesale, nationally:– No change; three integrated chains
• Locally:– Appr. 550 Ica stores acquired by Coop
– Many local markets affected
17.03.2016 Sørgard Merger Control University of Oslo 32
Which local markets?
• Screening of markets
– Coop 800 stores, Ica 550 stores
– Identified unproblematic local markets
• The parties no overlap
• Parties small compared to other chains
• All other chains are in the area
• Left with166 Ica- and 178 COOP stores in 125 geographic areas
17.03.2016 Sørgard Merger Control University of Oslo 33
Which local markets cont.
• Used data from a map program – Distance between parties’ stores
– Distance to the rivals’ stores
– Data on where cities and villages are
• Data from Coop on where their customers live
• Information about the stores: – Size
– Type of store
• Internal documents
17.03.2016 Sørgard Merger Control University of Oslo 34
GUPPI in remaining markets
• GUPPI= D12 ∗P2
P1∗ m2
• GUPPI over 3 %: Problematic market
• No prediction of price increase
• GUPPI can lead to:
– Higher prices
– Lower quality (opening hours and # of people employed)
• 𝐷12𝑐𝑟𝑖𝑡 = 0.03/(𝑚2 ∗ 𝑃2/𝑃1)
• Must also consider other factors
17.03.2016 Sørgard Merger Control University of Oslo 35
Relativ
margin
How to measure closeness of
competition?
• Asked shoppers, and from that estimated diversion ratios:
• “Tenk deg at du før avreise til butikken vissteat [konkret navn på butikken] var stengt, hvor ville du da handlet?
– Survey outside 60 stores with 200 respondents for each store
– Simple OLS models applied to find out what will affect closeness of competition in other local markets
17.03.2016 Sørgard Merger Control University of Oslo 36
DN 10.01.15: Study to detect
diversion ratios paid by COOP
17.03.2016 Sørgard Merger Control University of Oslo 37
How to find margins
• Which cost will vary with a small change in quantity sold?
• Input price
• Other costs (labour, distribution etc)
• Information from the parties used to estimate margin in each store
17.03.2016 Sørgard Merger Control University of Oslo 38
Other aspects
• Likely, efficient and timely entry– Generally high barriers to entry for new
players
– If other chains had entry plans, that taken into account
• Rivals’ response to a price increase– An argument for further price increase in
Bertrand market with differentiated products
• Savings on marginal costs– The parties the burden of proof
• (buyer power)
17.03.2016 Sørgard Merger Control University of Oslo 39
Coop/ICA: How it ended
• The parties had 1350 stores
• 125 areas identified after first
screening as problematic
• After a closer analysis, 90 areas
remained as problematic
– The method we have shown (UPP)
crucial for the choice of local markets
• The parties had to sell out 93 stores
17.03.2016 Sørgard Merger Control University of Oslo 40
Thank you!
17.03.2016 Sørgard Merger Control University of Oslo 41
Merger ControlExamples from practice
Jostein Skaar
April 13, 2016
Outline
UiO April 13 20162
Efficiencies
Market definition
Unilateral effects
• Egmont/CMore
• Telia Sonera/Tele 2
• Aleris/Teres
• Orkla/Cederroth
• Telia Sonera/Tele 2
• Sats/Elixia
1
2
3
CasesTopic Analysis
• Simple theory and facts
• Shock analysis
• UPP
• Cost estimates
• Type of efficiencies
• Welfare standard
Motivation:
Example from last week – presentation in Denmark
3 UiO April 13 2016
1. Unilateral effects
- Intuition for the method
- Our findings
2. ……….
Agenda
Unilateral effects
• When firm A raises its price, it looses customers to competing firms (grey arrows).
– How many customers e.g. Firm B gains, depends on how close a substitute Firm B’s product is (diversion).
• However, when Firm A raises its price, it also earns more money per customer. Firms “balance” these two effects in order to maximise profit.
5
Why do they matter in a merger?
Firm A
Firm B
Firm C
Firm D
Firm E
UiO April 13 2016
So what happens if Firm A and Firm B merge?
Unilateral effects
• If Firm A and Firm B merge, Firm A no longer looses all customers from the same price increase, because some of the customers go to Firm B.
– A price increase now becomes more profitable than before the merger.
– How much more profitable the price increase becomes, depends on the diversion from A to B (the size of the blue arrow).
– A larger diversion, all else equal, leads to a larger incentive to raise prices.
6
Why do they matter in a merger?
Firm A
Firm B
Firm C
Firm D
Firm E
UiO April 13 2016
Firms can regain lost profits from a price increase,
leading to an incentive to raise prices
What influences the magnitude of unilateral effects?
• Large diversion ratio = large pricing pressure
– Because the larger the diversion from A to B, the more profit Firm A can regain through Firm B
– End result: the more competitive (closer substitutes) Firm A and B are pre-merger, the higher the pricing pressure
• Margins matter for other firm’s pricing pressure
– Even if e.g. all customers go to Firm B if A raises its price, it will not be profitable if Firm B’s margin is zero.
– End result: The merged firms shift sales towards the relatively more profitable product.
7
The significance of diversion ratios and margins
Firm A
Firm B
Firm C
Firm D
Firm E
UiO April 13 2016
Unilateral effects of a XX – YY merger
8
• We find large pricing pressures for both XX and YY, given assumptions about:
– Diversion ratios
– Market size
– Margins
UiO April 13 2016
What if marginal costs (margins) change? This is a key assumption for our findings.
What happens if diversion
ratios are smaller?• Pricing pressures are reduced
• Despite assuming small
diversion ratios, the pricing
pressures remain large
What if the Market is larger?• Pricing pressure for YY increases,
because profit can be regained in
several (not just one) ………
• Pricing pressure for XX decreases,
as the diversion from YY is reduced
with more competitors
Market definition –Closeness of competition: Aleris/Teres – private hospitals
9 UiO April 13 2016
Who are competing – hospital services
10
• Main question: Are private hospitals like Aleris and Teres competing with publicly financed hospitals?
• Some information (facts) from the SO (Statement of Objection)
– Norway is divided into four health regions (North, Middle, South East and West)
– In each region the hospitals are owned by a separate regional business unit (RHF)
– The RHF is responsible for necessary health services to the population within the region
– In order to fulfill this obligation they buy services also from private hospitals
– Services from private hospitals are bought through tenders
UiO April 13 2016
More information from the SO
11
• Private hospitals compete for rights to supply hospital services that are publicly financed – by the RHF
• Private hospitals need to have a public concession in order to participate in the competition
• In this specific market Aleris and Teres have overlapping activities – orthopedics, plastic and obesity surgery
• After the tender has been concluded, private hospitals with agreements compete with public hospitals with regard to who actually performs the operation
• Competition between public and private hospitals if public hospitals also provide the relevant services
• Based on these facts the NCA defines a separate market for tenders from private hospitals –any competition from public hospitals will be considered later in the analysis – competition assessment
UiO April 13 2016
Our analysis - market share – public hospitals
12
Tabell 1: Markedsandeler (avrundet) offentlige sykehus – utvalg av alle DRG-er som er
knyttet til ortopedi, plastikk kirurgi og fedmekirurgi
Ortopedi Plastikk
kirurgi
Fedme-
kirurgi
Sør-Øst 99% 96% 97%
Vest 98% 96% 99%
Midt 96% 82% 86%
Nord 98% 96% 99%
Market shares – public hospitals – DRG points related to orthopedics, plastic and obesity surgery
UiO April 13 2016
RHF – optimal production
UiO April 13 201613
MC-public hospitals
With obligation to cover demand
DRG-financing
Production with no obligation and no use of private firms
• With no obligation to supply health care the
regional health unit would increase production
only until the marginal revenue (DRG-
financing) equals marginal cost – behaving as
a profit maximizing entity
• If they have an obligation (as they have - from
the owner – state) to produce more than this,
then their purpose would be to minimize cost to
reach the necessary level of production -
minimizing society cost involved in production
of health services
• If the marginal cost in production is higher than
what they have to pay private hospitals they
should buy services from private suppliers
Use of private hospitals 1
UiO April 13 201614
• Suppose that a private hospital can offer a price equal to the marginal cost of public production
– In this case the RHF should cancel he tender process and produce the necessary amount of services themselves
– If they accept the offer, they would have to pay more for the additional operations compared to own production – market area
Price- private
DRG-financing
Production with no obligation and no use of private firms
With obligation to cover demand
MC-public hospitals
Use of private hospitals 2
UiO April 13 201615
• The RHF should only accept the offer if the price is sufficiently below marginal cost
– Accept the offer if the blue area is less or equal to the orange area
• The private hospitals are disciplined directly by the alternative for public hospitals – own production
• There is competition between public and private hospitals in the tender market
Price- private
Production with no obligation and no use of private firms
With obligation to cover demand
MC-public hospitals
Competition in the «after» market
UiO April 13 201616
• Additional competition for patients after the tender has been concluded
• The private hospital has only won a right to treat patients with public financing – they would of cause try to supply as much as possible
• Knowing the price from private hospitals the RHF now are able to reduce cost more simply by treating patients where the marginal cost of own production is below the price offered and accepted by private hospitals
Price- private
Production with no obligation and no use of private firms
With obligation to cover demand
MC-public hospitals
Flexibility in public production
UiO April 13 201617
Change in number of DRG points in public hospitals from 2013 to 2014
Number of publicly financed DRG points in private hospitals
Tele 2/TeliaSonera (Telia)
18 UiO April 13 2016
TeliaSonera gets approval of Tele2 acquisition in Norway
UiO April 13 201619
“I am pleased that the Norwegian Competition Authority sees the advantages with this transaction. This is good, not only for our and Tele2's customers, but
also for Norway as a whole. We will be a stronger and more credible alternative to Telenor on their home market. We will now further accelerate the roll-out of
mobile Internet”
- Johan Dennelind, President and CEO of TeliaSonera
Horizontal merger – TeliaSonera/Tele2
Unilateral effects
Coordinated effects
TeliaSonera + Tele2
Commitments
Efficiencies
Welfare effects
Competition – markets for
mobile phone services
Wholesale market
End-user market
20 UiO April 13 2016
Tele 2 lost necessary frequency rights in 2014
UiO April 13 201621
In addition:
High roaming cost for Tele 2 irrespective of loss of frequencies
Possible agreement to use TeliaSonera’s network in the counterfactual situation
References – UPP analysis
UiO April 13 201622
• Farrell, J., & Shapiro, C. (2010). Antitrust Evaluation of Horizontal Mergers: An EconomicAlternative to Market Definition. The B.E. Journal of Theoretical Economics, 10(1).
• Hausman, J., Moresi, S., & Rainey, M. (2011). Unilateral effects of mergers with general linear demand. Economics Letters, 111, ss. 119-121.
• The European Commission. (2012). Case No COMP/M.6497 - Hutchison 3G Austria / Orange Austria. Strasbourg: The European Commission.
• Decision V2015-1 – Norwegian Compeititon Authority
Basic UPP analysis
UiO April 13 201623
TSN+T2
TSN Tele 2
𝑫𝑻𝟐,𝑻𝑺𝑵
PT2 - GUPPI: Measuring incentive to
increase price on one product
- UPP (Hausman et al.): Unilateral
effect – optimal change in price of
one product
Hausmans et al. (2011)'s UPP-framework
UiO April 13 201624
Assumptions
• Linear demand
• Equilibrium according to first order conditions before the merger
• Other firms hold their prices unchanged
First order cond. before merger
First order cond.after merger Calculating UPP
• Price pressure
estimated based on
optimal pricing after
the merger
• Two equations and two
unknown variables
(Δ𝑝1
𝑝1,Δ𝑝2
𝑝2)
UPP for both
firms
FOC after merger• Need only parameters
before the merger to
calculate first order
conditions after
• Parameters: prices, cost,
diversion ratios and
quantities sold before
the merger
Possible counterfactual situation
UiO April 13 201625
Adjusted UPP – TeliaSonera/Tele2
UiO April 13 201626
• Hausman et al. (2011) deduces a formula to calculate unilateral effects
– Marginal cost is the same for both firms before and after the merger
– Does not incorporate vertical relationship before the merger
• In our analysis of the TSN/Tele2 aquisition we assumed that:
1. Tele2 had significant roaming costs before the merger – after the merger, no roaming cost
2. Before the merger TSN received roaming payment from Tele2
• Hausman et al. (2011) compares the first order conditions before and after the merger
– We used the same basic method adjusted for 1. and 2. above – adjusted UPP
• Adjustment important for UPP calculations
– Reduction in marginal cost implies a significant lower UPP for Tele2
– Roaming income received by TSN reduces the price pressure for TSN significantly
UiO April 13 201627
Assumptions –Tele2`s marginal cost after the merger
No change in MC No NRA or MVNO cost after the mergerAssumptions – counterfactual
scenario
Tele2 - MNO: Historic market shares, NRA prices and traffic
Tele2 - MVNO (1):No strategic links to TSN
Tele2 - MVNO (2): Strategic links to TSN through MVNO agreement
𝑼𝑷𝑷𝑴𝑪+ 𝑹𝑪𝑴𝑵𝑶 𝑼𝑷𝑷𝑴𝑪
𝑴𝑵𝑶
𝑼𝑷𝑷𝑴𝑪+ 𝑹𝑪𝑴𝑽𝑵𝑶 𝒏𝒐 𝒍𝒊𝒏𝒌 𝑼𝑷𝑷𝑴𝑪
𝑴𝑽𝑵𝑶 𝒏𝒐 𝒍𝒊𝒏𝒌
𝑼𝑷𝑷𝑴𝑪+𝑹𝑪𝑴𝑽𝑵𝑶 𝒍𝒊𝒏𝒌 𝑼𝑷𝑷𝑴𝑪
𝑴𝑽𝑵𝑶 𝒍𝒊𝒏𝒌
Tele2 and ICE - MNO: New NRA prices and strategic link to TSN 𝑼𝑷𝑷𝑴𝑪+ 𝑹𝑪
𝑴𝑵𝑶𝒘𝒊𝒕𝒉 𝑰𝑪𝑬 𝑼𝑷𝑷𝑴𝑪𝑴𝑵𝑶𝒘𝒊𝒕𝒉 𝑰𝑪𝑬
Comparing the standard UPP with the adjusted UPP
UiO April 13 201628
Reality
UPP
Time
𝑡1
𝑡2
price
cost
diversion
quantity
price
cost
diversion
quantity
Input data
Estimate: Price
pressure
Estimate: Price
pressure
UPP adjusted
1 2
Use an equilibrium model to test the two different indicators (based on Shubik & Levitan utility function)……
Merger between two vertically integrated firms – no change in marginal cost
UiO April 13 201629
Merger between two vertically integrated firms – change in marginal cost
UiO April 13 201630
One firm closes down the upstream activity and starts to buy input from a competing firm
UiO April 13 201631
Merger between firms with vertical relationship
UiO April 13 201632
Concluding remarks
UiO April 13 201633
Adjusted UPP
UPP (Hausman)
Step1:
Step2:
Step 1&2 (Δ𝑐2):
Estimates too high price pressure on product 2. Too high or too low price pressure on product 1.
Wrong estimates of price pressure on both products if asymmetric diversion ratios.
Results equal to the equilibrium model
N/A
One firm closes down the up-stream activity and starts to buy input from a competing firm
Merger between the firms in step 1
Merger between two vertically integrated firms –change in marginal cost
Unilateral effects – Sats/Elixia
UiO April 13 201634
Need marginal cost to calculate margins….
UiO April 13 201635
• Suppose that marginal cost is equal to average variable cost (Case No COMP/M.6497 -Hutchison 3G Austria / Orange Austria.)
• Identify the cost components that vary with a small change in production…..
• If 100% variable – average variable cost = marginal cost
• …it is not always obvious which costs that vary with production and how much
• Alternative solution used in the SATS/ELIXIA case (Finland)
– Use econometrics to estimate variable cost
Illustration – estimating variable cost
UiO April 13 201636
• Historic cost levels and volumes for one firm with two branches
• The blue lines represent the result of the regression analysis where the cost level is explained by volume
• Assuming constant marginal cost, the regression coefficient will be an estimate of marginal cost
• Two types of analysis – OLS and Fixed Effects – which is the right one?
0
200000
400000
600000
800000
1000000
500 1500 2500 3500 4500
0
200000
400000
600000
800000
1000000
500 1500 2500 3500 4500
Shock analysis – Orkla/Cederroth
UiO April 13 201637
Close competitors?
38 UiO April 13 2016
Estimating diversion ratios using shock analysis
UiO April 13 201639
See paragraph 165 and 166 in decision V2015-30
𝐷𝑁𝑆𝑖𝑛𝑐𝑟𝑒𝑎𝑠𝑒𝑑 𝑠𝑎𝑙𝑒𝑠 𝑜𝑓𝑆𝑎𝑚𝑎𝑟𝑖𝑛
𝑟𝑒𝑑𝑢𝑐𝑒𝑑 𝑠𝑎𝑙𝑒𝑠 𝑜𝑓𝑁𝑦𝑐𝑜
Welfare standard – Egmont/CMore
UiO April 13 201640
Overlapping business between TV2 and C More
41
Sports
Pay-TV
Film andseries
Commercial channels
Film
Streaming
UiO April 13 2016
Tippeligaen and Premier League is not competing products
42
jan.
09
mar.
09
mai.0
9
jul.0
9
sep
.09
nov.
09
jan.
10
mar.
10
mai.1
0
jul.1
0
sep
.10
nov.
10
jan.
11
mar.
11
mai.1
1
jul.1
1
sep
.11
nov.
11
jan.
12
mar.
12
mai.1
2
jul.1
2
sep
.12
nov.
12
jan.
13
mar.
13
mai.1
3
jul.1
3
sep
.13
nov.
13
jan.
14
mar.
14
mai.1
4
jul.1
4
sep
.14
nov.
14
TV 2 (Sport + Premium) C More (Total + Sport) TV2 + C More
• TL and PL had most subscribes at the time when TV2 controlled both rights
• Indicates that the non-competing rights are most efficiently used when the same player controls both set of rights
TV2-TL, C More PL TV2 TL & PL TV2 PL, C More TL
UiO April 13 2016
Efficiencies – TeliaSonera/Tele2
UiO April 13 201643
TeliaSonera gets approval of Tele2 acquisition in Norway
UiO April 13 201644
“I am pleased that the Norwegian Competition Authority sees the advantages with this transaction. This is good, not only for our and Tele2's customers, but
also for Norway as a whole. We will be a stronger and more credible alternative to Telenor on their home market. We will now further accelerate the roll-out of
mobile Internet”
- Johan Dennelind, President and CEO of TeliaSonera
Three types of efficiencies
UiO April 13 201645
1. Dynamic efficiencies – more customers increase the incentive to invest
– Increased quality and new products
– Closer to Telenor – more competition
2. Reduced variable cost – incentive to compete more aggressively on price
3. Lower fixed cost – able to maintain production level using less resources
Hvor store gevinster skal til?
UiO April 13 201646
• http://www.tu.no/artikler/teliasonera-kjoper-tele2/231087:
«The company expects synergies of at last 800 SEK from 2016.»
• How much need to be considered a gain to society?
– Simple calculation based on possible price increase, margin, elasticity of demand and market size
– Price increase of (p) 5%, margin (m) 50%, elastisity (e) -0,25 and a market of 15 mrd –dead weight loss of 100 mill.
– dead weight loss % 𝑜𝑓 𝑡𝑢𝑟𝑛𝑜𝑣𝑒𝑟𝑒×𝑝2
2+𝑚 × 𝑝 × 𝑒
www.osloeconomics.no
Tore Nilssen – Strategic Competition – Theme 7 – Slide 1
Information and strategic interaction Assumptions of perfect competition: (i) agents (believe they) cannot influence the market
price (ii) agents have all relevant information What happens when neither (i) nor (ii) holds? Strategic interaction among a group of firms where some or all are incompletely informed In particular: What happens when a firm knows more than the others about demand, own costs, etc.? Equilibrium outcome is now also determined by incompletely informed firms’ beliefs. These beliefs are represented by subjective probabilities. (i) Incomplete information in a static model
- how beliefs determine the equilibrium
(ii) … in a dynamic model - how beliefs are formed
Tore Nilssen – Strategic Competition – Theme 7 – Slide 2
Games with incomplete information Perfect Bayesian Equilibrium: Both strategies and beliefs are in equilibrium. • Given the strategies in equilibrium, which revised beliefs
are consistent with these strategies? • Given the beliefs in equilibrium, which strategies are in
equilibrium? Two different kinds of problem: • Asymmetric information – and the importance of the
uninformed firm observing the informed firm’s actions. • Symmetric, incomplete information – and how there still
may be a lot of action even though firms cannot observe each other’s actions.
Signalling A typical signalling game: Stage 1: The informed player chooses an action (signals) Stage 2: The uninformed player observes stage 1, revises his beliefs about the informed player, and chooses an action himself. The informed player’s private information – his type
θ ∈ {High, Low}
Tore Nilssen – Strategic Competition – Theme 7 – Slide 3
The uninformed player’s beliefs about the other’s type: Initial beliefs Pr(High) = pH Pr(Low) = pL = 1 – pH Stage 2: revised beliefs Equilibrium: actions and revised beliefs Separating equilibrium: the action taken by the informed player at stage 1 depends on his type. Pooling equilibrium: the action taken by the informed player at stage 1 is independent of his type. In a pooling equilibrium, the uninformed player learns nothing about the other player’s type from observing his stage-1 action. Beliefs cannot be updated based on that action. In a separating equilibrium, on the other hand, the stage-1 action reveals the informed player’s type, and so, based on that action, the uninformed player can update his beliefs about the other player’s type and act accordingly.
Tore Nilssen – Strategic Competition – Theme 7 – Slide 4
First – a static model: Price competition with asymmetric information Two firms. Product differentiation. Price competition. Product differentiation: A slight increase in a firm’s price causes a slight decrease in its demand and a slight increase in the other firm’s demand. D1 = D1(p1, p2); D2 = D2(p2, p1)
− + – + Firm 1 has private information about own costs. Both firms know firm 2’s costs. Firm 1’s unit costs: c1 = Lc1 , with probability x
c1 = Hc1 , with probability (1 – x) Lc1 < Hc1
Firm 2 only knows the probability distribution (Lc1 , Hc1 , x) Firm 1 knows both c1 and the probability distribution.
Tore Nilssen – Strategic Competition – Theme 7 – Slide 5
In the case of complete information: π1 = (p1 – c1)D1(p1, p2)
( ) ( ) ( )0
,,
1
21111211
1
1 =∂
∂−+=∂∂
p
ppDcpppD
p
π
Best response of firm 1: R1(p2). Slope of the best response:
sign R1’(p2) = sign 21
12
pp ∂∂∂ π
.
( ) ( ) ( )
21
2112
112
211
21
12 ,,
pp
ppDcp
p
ppD
pp ∂∂∂−+
∂∂=
∂∂∂ π
• First term positive
• Slope of the best response positive unless 21
12
pp
D
∂∂∂
very
negative.
Tore Nilssen – Strategic Competition – Theme 7 – Slide 6
Equilibrium with complete information:
R2(p1)
R1(p2) p2
p1
Tore Nilssen – Strategic Competition – Theme 7 – Slide 7
The optimum p1 is increasing in c1:
0111
12
121
12
=∂∂
∂+∂∂
dccp
dpp
ππ
0211
211
211
2111
2
1
1 >∂∂∂∂=
∂∂∂∂∂−=
p
pD
p
cp
dc
dp
πππ
HR1
R2
LR1 p2
p1
Tore Nilssen – Strategic Competition – Theme 7 – Slide 8
Firm 2 doesn’t know firm 1’s type. Firm 2 behaves as if confronting an expected firm 1. Analytically, we find three prices:
The price of the uninformed firm. The price of the informed firm if it has high costs. The price of the informed firm if it has low costs.
eR1
*1Hp
*1Lp
p2*
HR1
R2
LR1 p2
p1
Tore Nilssen – Strategic Competition – Theme 7 – Slide 9
How is the equilibrium affected by incomplete information? If firm 1 is low-cost, then incomplete information increases the equilibrium prices. If firm 1 is high-cost, then incomplete information reduces the equilibrium prices. Probability of firm 1 being low-cost: x An increase in x reduces equilibrium prices, whether firm 1 is low-cost or high-cost. If firm 1 could choose x, it would want x to be low, whether the firm actually is low-cost or high-cost. • The informed firm would like to be believed to have high
costs, because that would keep prices high.
Tore Nilssen – Strategic Competition – Theme 7 – Slide 10
Dynamic model Stage 1: An action by firm 1 that may potentially influence firm 2’s subjective probability that firm 1 is low-cost. Stage 2: Price competition with asymmetric information What action? (i) Verifying costs – external audit
Verification is good for firm 1 if it is high-cost, but not if it is low-cost.
(ii) Verification not possible Model: Two-period price competition between two firms Period 1: Price competition Period 2: Price competition Is it possible for firm 2 to infer firm 1’s cost from firm 1’s price in stage 1? In period 1, a high-cost firm 1 would want to set a price that reveals its cost, while a low-cost firm 1 would not want to reveal its cost.
Tore Nilssen – Strategic Competition – Theme 7 – Slide 11
Signalling game. Could it be possible for a high-cost firm 1 to set a price in period 1 that is so high that a low-cost firm 1 would not want to mimic it? – Yes, because increasing the price is less costly for a high-cost firm than for a low-cost firm. π1 = (p1 – c1)D1(p1, p2)
01
1
11
12
>∂∂−=
∂∂∂
p
D
cp
π
The effect on firm 1’s profit of a price increase depends on the firm’s costs. The higher costs are, the stronger is the effect if it is positive, and the weaker is the effect if it is negative.
p1
π1
high-cost
low-cost
Tore Nilssen – Strategic Competition – Theme 7 – Slide 12
A separating equilibrium is one where firm 1’s price in period 1 depends on its costs. A pooling equilibrium is one where firm 1’s price in period 1 is the same whether it is low-cost or high-cost. If firm 1’s price in period 1 reveals its costs, then there is complete information in period 2. If firm 1’s price in period 1 is uninformative of its costs, then the period-2 game is as in the static model. Firm 1 would want firm 2 to believe it is high-cost, whether this is true or not.
R2
HR1 LR1 p2
p1
Tore Nilssen – Strategic Competition – Theme 7 – Slide 13
Firm 2 will only believe firm 1 is a high-cost firm if it sets a price in period 1 that is so high that a low-cost firm would never set it – even though, by doing so, it would be considered a high-cost firm in period 2. Thus, in a separating equilibrium, the high-cost best-response curve in period 1 is further to the right than in the static model. Therefore, the expected best-response curve shifts to the right, and all prices are higher in period 1 of the two-period model than in the static model. An extension: each firm has private information about own costs. The result that prices are higher still holds. [Mailath, ”Simultaneous Signaling in an Oligopoly Model”, Quart J Econ 1989]
High-cost firm sets high price today in order to induce a high price tomorrow. → Puppy Dog strategy
p2
p1
Tore Nilssen – Strategic Competition – Theme 7 – Slide 14
Entry deterrence Top Dog strategy Two periods. Firm 1 has private information about own costs. Period 1: Firm 1 is monopolist. It cannot deter entry through capacity investments, etc. Can it deter entry through its period-1 price? Firm 1 wants firm 2 to believe its costs are low.
01
2 >∂∂
c
π, 02 <
∂∂
x
Eπ
The interesting case: Entry is profitable for firm 2 if firm 1 has high costs but not if it has low costs. Reducing the price is less costly for a low-cost firm than for a high-cost firm.
p1
π1
high-cost
low-cost
Tore Nilssen – Strategic Competition – Theme 7 – Slide 15
Complete information: Period-1 price is the monopoly price. Firm 2 enters if and only if firm 1 has high costs. Incomplete information: One of two situations may occur. (i) Low-cost firm 1 sets a price below its monopoly
price, in order to signal its low costs. • Separating equilibrium
(ii) Both types of firm 1 set the low-cost monopoly
price. • Pooling equilibrium • Can only happen if firm 2, without any new
information, is deterred from entry. Limit pricing: Price reduction to deter entry. Is limit pricing credible? In case (i), it is. The price reduction in the separating equilibrium serves to inform the potential entrant that entry is not profitable because of the presence of a very potent incumbent. In case (ii), it is not. However, the outside firm hasn’t learned anything during period 1 and therefore chooses to stay out.
Tore Nilssen – Strategic Competition – Theme 7 – Slide 16
What are the welfare consequences of incomplete information? In both cases: Expected price lower because of incomplete information. In case (i) – separating equilibrium – entry behaviour is unaffected by incomplete information. Thus, with a separating equilibrium, incomplete information is good for welfare. In case (ii) – pooling equilibrium – the high-cost firm 1 manages to deter entry by mimicking the low-cost type. Thus, incomplete information implies less entry. Total effect on welfare is unclear. What if the entrant does not know its own costs? Suppose firms’ costs are the same, but only firm 1 knows what they are.
02 <∂
∂c
π
Firm 1 wants to signal high costs in order to deter entry. Now, the high-cost firm sets price above monopoly price in order to deter entry. Puppy Dog as entry deterrence. [Harrington, ”Limit Pricing When the Potential Entrant Is Uncertain of Its Cost Function”, Econometrica 1986]
Tore Nilssen – Strategic Competition – Theme 7 – Slide 17
Incomplete information and unobservable action • Rival’s price is unobservable
(recall Green & Porter)
• Incomplete information about demand • Symmetric information: Both firms incompletely
informed • Learning over time
- Collecting information today in order to have more knowledge about demand tomorrow
• Strategic aspects of learning
- A firm may try to disturb the other firm’s learning today in order to affect future decisions
Model: Two firms. Two periods. Product differentiation. Price competition each period.
- Prices are strategic complements. Firms do not observe each other’s prices. Firms do not know the market demand function.
qi = a – pi + bpj
Tore Nilssen – Strategic Competition – Theme 7 – Slide 18
• Firm A wants firm B to set a high price in period 2. • Firm B will only set a high price in period 2 if it believes
demand is high. • Firm B may think demand is high if it has high sales in
period 1. • Firm A may set a high price today in order for firm B to
believe demand is high. • But also firm B reasons the same way about firm A. • And each firm also knows the other firm manipulates its
learning. • Both firms set high prices in period 1 in order to
manipulate each other’s learning. • But each firm is able to see through the other firm’s
manipulation and learns the correct demand condition before period 2.
• Signal-jamming: manipulating others’ learning • In our case: signal-jamming increases period-1 prices.
Tore Nilssen – Strategic Competition – Theme 7 – Slide 19
Signal-jamming
� � �
termstochastic
firm by thecontrolled
other by theobserved
εα +=s
Other applications: Organizational economics, corporate governance
– moral hazard A specific model: Firms: I and II No costs. Demand: Di(pi, pj) = a – pi + pj, i ≠ j. No firm knows a, only its expected value: ae = Ea The one-period case: (Benchmark) Each firm solves:
( ){ } ( ) ijie
ijiip
pppapppaEEi
+−=+−=πmax
Best-response function: 2
je
i
pap
+=
Equilibrium: pI = pII = ae.
Tore Nilssen – Strategic Competition – Theme 7 – Slide 20
The two-period case: Learning about a if other firm’s price is observable: a = Di + pi – pj But other firm’s price is not observable
��
termstochastic
firmby controlled
firmby observed
appD
j
j
i
ii +=+���
In a symmetric equilibrium, each firm sets the same price in equilibrium, α, so that: Di = a – α + α = a But which price? If firm II sets the price α and believes firm I does the same, what price would firm I want to set? Firm II ’s estimate of a after period 1:
1~IIDa = = a – α + 1
Ip → ( )1~~Ipaa =
In period 2, firm II believes it is playing a game of complete information where a = ( )1~
Ipa .
→ ( )12 ~III pap =
Tore Nilssen – Strategic Competition – Theme 7 – Slide 21
What are the incentives for firm I to set a price in period 1 that differs from α? First, consider period 2: Firm I has been able to deduce the true a and solves:
( )[ ] 212 ~max2 IIIp
ppapaI
+−
→ ( )
222
~ 1112 αα −+=+−+=+= IIII
pa
paapaap
Firm I’s period-2 profit:
21
2
2
−+= απ II
pa
Period 1: What is the optimum price for firm I in period 1, given firm II ’s price α? Discount factor: δ ∈ (0, 1] Firm I solves:
( )
−+++−21
11
2max
1
αδα III
ap
pappaE
I
Tore Nilssen – Strategic Competition – Theme 7 – Slide 22
FOC: 02
21
1 =
−+++− αδα IeI
e papa
In a symmetric equilibrium: 1Ip = α. ae – 2α + α + δae = 0 ⇒ First-period price: α = ae(1 + δ) • Manipulation of learning fails. • The firms set higher prices in period 1 than if
manipulation of each other’s learning were not possible. • Puppy-dog strategy: A high price today in order for the
other firm to believe demand is high and therefore set a high price tomorrow.
Tore Nilssen – Strategic Competition – Theme 7 – Slide 23
Strategic interaction in one market – incomplete information in another A version of predation: The stronger firm competes aggressively in order to reduce the weaker firm’s financial resources.
Product market: Duopoly – complete information Capital market: Competitive – incomplete information Two periods. The two firms differ in financial strength: The “long purse” story. In order to operate in the market in period 2, each firm has to incur an investment K. Firm 1 has internal funds in excess of K. Firm 2 has to borrow on the capital market: Its internal funds equal E < K. Firm 2 borrows D = K – E, and has to pay back: D(1 + r) Interest rate: r
Tore Nilssen – Strategic Competition – Theme 7 – Slide 24
Firm 2’s gross profit in period 2 is stochastic: π~ ∈ [π,π ] Cumulative distribution function: F(π~); F’(π~) = f(π~) Expected value: πe
If π < D(1 + r), then firm 2 goes bankrupt. Bankruptcy: The bank receives π and incurs bankruptcy costs B. Competitive capital market – banks’ profits 0. Banks’ cost of funds: r0
The interest rate in equilibrium solves:
( ) ( )( )[ ] [ ] ( )( )
( )DrdfBrDFDrrD
0
1
1~~~111 +=−++−+ ∫+
ππππ
The expected bankruptcy costs will have to be covered by the borrowers. So firm 2’s capital costs is [(1 + r0)E] + [(1 + r0)D + BF(D(1 + r))] = (1 + r0)K + BF((K – E)(1 + r))
Tore Nilssen – Strategic Competition – Theme 7 – Slide 25
Firm 2’s expected net profit in period 2: W = πe – (1 + r0)K – BF((K – E)(1 + r)) The higher is firm 2’s internal funds, the more likely is it that firm 2 will undertake the period-2 investment: An increase in E
- lowers debt K – E - lowers interest rate r
Thus: 0>dE
dW
Period 1: • E is a function of firm 2’s period-1 profits. • Firm 1 can lower E by reducing prices in period 1. • Predatory pricing.
Tore Nilssen – Strategic Competition – Theme 8 – Slide 1
Research and development (R&D) What will a market look like in the future?
- which firms? - which products? - which production technology?
Depends on:
- entry deterrence, mergers, etc. - regulation - consumers’ preferences - innovation ← - …
Two kinds of innovation • Product innovation • Process innovation Product innovation a special case of process innovation?
Tore Nilssen – Strategic Competition – Theme 8 – Slide 2
Process innovation What is the value of an innovation?
- for society - for the innovating firm
It depends on the situation. Patents: protecting inventions Consider a firm making an innovation that is patent-protected forever. Constant unit costs. The innovation reduces costs from c to c, c > c. The value to a social planner
( )∫= c
cs dccD
rV
1
c D(p)
Tore Nilssen – Strategic Competition – Theme 8 – Slide 3
The private value (1) monopoly
π(p, c) = (p – c)D(p)
pm(c) = argmaxp π(p, c)
πm(c) = π(pm(c), c)
( ) ( )c
cp
cdc
dp
pdc
cd mmm
∂∂=
∂∂+
∂∂= ,ππππ
= – D(pm(c))
pm(c) > c, ∀ c ⇒ D(pm(c)) < D(c), ∀ c.
( )( ) sc
cmm VdccpD
rV <= ∫
1
Private value is less than social value
Tore Nilssen – Strategic Competition – Theme 8 – Slide 4
(2) competition Suppose all firms in the market have constant unit costs c . Homogeneous products. Price competition. p = .c π = 0. One firm makes an innovation, getting c = c. Two cases to consider: (i) The innovation is drastic: pm(c) ≤ c .
Even at the monopoly price, the innovating firm takes the whole market.
(ii) The innovation is non-drastic: pm(c) > c .
Also now, the innovating firm takes the whole market, but has to set p = c .
Tore Nilssen – Strategic Competition – Theme 8 – Slide 5
Consider a non-drastic innovation.
πc = (c – c)D(c )
( ) ( ) ( )∫=−= c
cc dccD
rcDcc
rV
11
∀ c > c, pm(c) > pm(c) > c ⇒ D(pm(c)) < D(c ), ∀ c > c. ⇒ Vm < Vc. D(c ) < D(c), ∀ c < c . ⇒ Vc < Vs ⇒ Vm < Vc < Vs
Exercise 10.1: This ranking also holds for drastic innovations
Tore Nilssen – Strategic Competition – Theme 8 – Slide 6
Why is Vm < Vc? The replacement effect of an innovation. (Arrow, 1962) In the competition case, the innovating firm escapes a zero-profit situation. In the monopoly case, the innovating firm replaces one monopoly situation with another one. Because of the replacement effect, competition is good for firms’ incentives to innovate. Exercises 10.2, 10.3.
Tore Nilssen – Strategic Competition – Theme 8 – Slide 7
(3) a monopolist threatened by entry Suppose the entrant innovates in case the monopolist does not. This increases the monopolist’s incentives to innovate, since now the alternative is worse. πd(c1, c2) – profit per period in a duopoly when own cost is c1 and rival’s cost is c2. If the monopolist does not innovate and the other firm enters and does innovate, then the monopolist earns πd(c , c) and the new firm earns πd(c, c ). Assumption: πm(c) ≥ πd(c , c) + πd(c, c ) Value of the innovation for the monopolist:
Vm = r
1[πm(c) – πd(c , c)]
⇒ Vm – Vc = r
1[πm(c) – πd(c , c) – πd(c, c )] ≥ 0
Opposite ranking, because of the efficiency effect: a monopolist earns more than two duopolists.
Tore Nilssen – Strategic Competition – Theme 8 – Slide 8
The two effects:
- the replacement effect
- the efficiency effect
Patent race
Two firms, incumbent and potential entrant, fight to be first to make an innovation with an ever-lasting patent.
The more valuable the innovation is for the incumbent, the more resources it spends on being first, and the greater is the probability that it will win the race and get even more control over the market.
If the efficiency effect dominates the replacement effect, then Vm > Vc and the incumbent gets even more control over the market.
Opposite, if Vc > Vm, then the entrant takes over, at least in expectation.
Tirole, Sec. 10.2
Tore Nilssen – Strategic Competition – Theme 8 – Slide 9
Strategic technology adoption Technology without patent protection. Technology adoption is costly. Two firms, homogeneous products. Constant unit costs c . Zero profits. Low-cost technology is available: c < c Non-drastic innovation: If only one firm adopts the new technology, then it earns c – c per unit per period. Assume: D(c ) = 1.
Value of innovation: V = r
cc −
Value for non-innovating firm: 0. Costs of adoption ⇒ A firm will not want to adopt if the other one has already adopted. Strategic incentives to adopt early. But what happens when both know they both have such incentives? Adoption costs are decreasing over time: C(t),
C(0) very high, C’( t) < 0, C’’( t) > 0.
Tore Nilssen – Strategic Competition – Theme 8 – Slide 10
Net present value of adopting new technology at time t, given that none of the firms adopted before time t, is: L(t) = [V – C(t)]e-rt This is the value of being technology leader. The follower does not adopt: F(t) = 0, ∀ t. (i) The technology leader picked in advance –
technology adoption without strategic considerations.
The leader maximizes L(t):
( ) ( ) ( )[ ] 0''
delay fromcost marginal
delay fromgain marginal
=
−−−= −rtetCVrtCtL��������
C(t*) = V + ( )r
tC *' < V
(ii) Strategic considerations Both firms consider technology adoption Define tc by: L(tc) = 0 ⇒ C(tc) = V ⇒ tc < t*
Tore Nilssen – Strategic Competition – Theme 8 – Slide 11
A firm never adopts before tc. The best response to the other firm’s adoption at t’ > tc is to adopt at t ∈ (tc, t’). The best response to the other firm’s adoption at tc is not to adopt at all. The best response to the other firm not adopting is to adopt at t* > tc. The only possible equilibrium is one in mixed strategies. At each point t, each firm has a subjective probability p(t) that the other firm adopts the technology at t, given that none of the firms has adopted so far. In equilibrium, the firms are indifferent between adopting and not at each t ≥ tc. Payoff to each firm if they both adopt at time t:
B(t) = – C(t)e-rt Equilibrium condition: L(t)[1 – p(t)] + B(t)p(t) = F(t) [V – C(t)][1 – p(t)] – C(t)p(t) = 0
⇒ p(t) = 1 – ( )
V
tC, t ≥ tc
• A strong strategic incentive for adoption • But what if profits are positive with competition?
- product differentiation?
Tore Nilssen – Strategic Competition – Theme 8 – Slide 12
Network externalities Positive externalities between consumers Example: telephone, telefax More generally: network effects Example: system goods, such as
- computers / software, - DVD players / DVDs
When a new technology is available, each consumer must decide whether to switch. A coordination problem: the more consumers switching, the higher is the utility for each from switching. Excess inertia: consumers wait longer than what is socially optimum because no-one wants to be first to switch to the new technology. Excess momentum: consumers switch too early because they do not want to be left with the old technology. On the supply side:
- which technology to offer? - standardization of new technology - compatibility with other products
Tore Nilssen – Strategic Competition – Theme 8 – Slide 13
A model of consumer behaviour with network externalities Two consumers. Two technologies: old and new. q = network size ∈ {1, 2} u(q) = a consumer’s utility with old technology v(q) = a consumer’s utility with new technology Positive network externalities: u(2) > u(1), v(2) > v(1) Better to be together than separate: u(2) > v(1), v(2) > u(1)
Consumer 2 New Old
Consumer 1 New v(2), v(2) v(1), u(1) Old u(1), v(1) u(2), u(2)
Two pure-strategy equilibria: {New, New} and {Old, Old}. Excess inertia: If the consumers play {Old, Old} and v(2) > u(2). Excess momentum: If the consumers play {New, New} and v(2) < u(2).
Tore Nilssen – Strategic Competition – Theme 8 – Slide 14
A more sophisticated model Dynamic analysis: Two periods. Incomplete information about the other consumer’s preferences. A consumer of type θ has preferences
uθ(q) and vθ(q), q ∈ {1, 2}, θ ∈ [0, 1]. The higher θ is, the more interested the consumer is in switching to new technology:
( ) ( )[ ]
012 >−
θθθ
d
uvd
Network externalities: uθ(2) > uθ(1), ∀ θ; vθ(2) > vθ(1), ∀ θ. The highest θ-type prefers switching even if he is alone: v1(2) > v1(1) > u1(2) > u1(1) The lowest θ-type is the opposite: u0(2) > u0(1) > v0(2) > v0(1) • Coordination problems only for consumer types in the
middle range. Consumers are independently and uniformly distributed on [0,1].
Tore Nilssen – Strategic Competition – Theme 8 – Slide 15
Four possible strategies for a consumer: (1) Never switch (2) Do not switch in period 1; switch in period 2
regardless of what happened in period 1. (3) Do not switch in period 1; switch in period 2 if and
only if the other consumer switched in period 1. (4) Switch in period 1. Strategy (2) is dominated by strategy (4).
• Strategy (4) never fares worse than (2), and if the opponent plays strategy (3), then strategy (4) is strictly better than (2).
Equilibrium play depends on θ: 0 θ* θ** 1 A consumer of type θ* is indifferent between the old technology with a small network and the new technology with a big network: uθ*(1) = vθ*(2)
θ never (1)
jump on the bandwagon
(3)
immediately (4)
Tore Nilssen – Strategic Competition – Theme 8 – Slide 16
A consumer of type θ** is indifferent between: (a) switching to a big network only if the other consumer
switched in period 1, and otherwise staying in a big network; and
(b) switching in period 1, implying being in a small network if the other consumer plays strategy (1) and in a big network otherwise
vθ** (2)(1 – θ**) + uθ** (2)θ** = vθ** (1)θ* + vθ** (2)(1 – θ*) ⇔ [vθ** (2) – uθ** (2)]θ** = [ vθ** (2) – vθ** (1)]θ* ⇒ vθ** (2) > uθ** (2) Excess inertia may occur: In the case where both consumers have θs just below θ**, no-one switches to the new technology because they play the jump-on-the bandwagon strategy, even if vθ(2) > uθ(2). The supply side Stage 1: Each firm decides whether its product is to be compatible with rival firms’ products. Stage 2: Price or quantity competition. Trade-off: Compatibility implies a larger market, but tougher competition.
Tore Nilssen – Strategic Competition – Theme 9 – Slide 1
Vertical relations Products are sold through retailers. How does this affect market performance? pw – wholesale price
p – retail price Demand: q = D(p)
Contracts producer-retailer One extreme: vertical integration – producer and retailer act as if they are one firm The other extreme: linear price – total price is T(q) = pwq
p
pw
c
Producer
Retailer
Tore Nilssen – Strategic Competition – Theme 9 – Slide 2
Two-part tariff total price is T(q) = A + pwq price per unit decreasing in q – quantity discount A – franchise fee Resale price maintenance Producer determines the retail price. US Supreme Court: The Leegin case (2007) Variations: price ceiling, price floor. Exclusive dealing Retailer is not allowed to carry competing producers’ products. (inter-brand competition) Exclusive territories Retailer has the sole right to sell the producer’s products within a specified area. (intra-brand competition) Arguments for vertical integration • the theory of the firm – Ronald Coase • transaction costs • incentives for relationship-specific investments • we focus here on other arguments
Tore Nilssen – Strategic Competition – Theme 9 – Slide 3
Vertical externalities • Double marginalization If both producer and retailer are monopolists, then quantity sold is less than if they were integrated. pw > c ⇒ pm(pw) > pm(c) Example: D(p) = 1 – p, c < 1 (i) No integration The retailer solves: maxp πr = (p – pw)(1 – p)
2
1 wpp
+=⇒ 2
1 wpq
−=⇒
The producer solves:
( )2
1max w
wpp
pcp
w
−−=π
2
1 cpw
+=⇒ 4
1 ,
43 c
qc
p−=+=⇒
Total profit: ( ) ( ) ( )2
22
1163
161
81
ccc
rpni −=−+−=+= πππ
Tore Nilssen – Strategic Competition – Theme 9 – Slide 4
(ii) Integration The integrated firm solves: maxp πi = (p – c)(1 – p)
2
1 ,
43
21 c
qcc
p−=+<+=⇒
Profit: ( ) nii c ππ >−= 2141
Both the two firms and society would gain from integration. Alternatives to full integration (a) two-part tariff T(q) = A + pwq
The producer can set: pw = c, ( )
41 2c
A−=
Interpretation: Sell the whole business to the retailer for a price equal to monopoly profit – the retailer becomes the residual claimant. But: - risk-sharing: what if D(p) is uncertain and the retailer is
risk averse? - asymmetric information about D(p)
Tore Nilssen – Strategic Competition – Theme 9 – Slide 5
(b) resale price maintenance Producer restricts retail price: p ≤ pm, sets wholesale price: pw = pm. But again: risk sharing Other externalities - retailer service The retailer may, by putting in promotion effort, increase the demand for the product. But some of the increase in demand will benefit the producer. Two-part tariff still works (but: risk sharing?) Resale-price maintenance is not sufficient:
The producer would want to control the service level, too.
- input substitution
Tie-in: producer sells both inputs to the retailer.
Tore Nilssen – Strategic Competition – Theme 9 – Slide 6
A horizontal externality Several retailers. One retailer’s advertising effort benefits also the other retailers. The producer needs to encourage such efforts in order himself to benefit from this externality. Two-part tariff with pw < c Retailer power What if the retailer has the bargaining power? Example: the Norwegian grocery industry. Gabrielsen & Sørgard, “Discount Chains and Brand Policy”, Scandinavian Journal of Economics 1999. Johansen & Nilssen, “The Economics of Retailing Formats: Competition versus Bargaining”, Journal of Industrial Economics 2016.
Tore Nilssen – Strategic Competition – Theme 9 – Slide 7
Vertical foreclosure • A firm has control over the production of a product or
service that is an essential input for producers in a potentially competitive industry. The competition in this industry can be altered by the firm by denying or limiting access to the input.
• Essential facility
- bottleneck - network industries: firms need access to network to
deliver product or service � telecom: AT&T, Telenor � power: Statnett � shipping: harbours � railway: Eurotunnel
- outside network industries: firms are at a disadvantage without access
� computer reservation systems for airlines � cooperatives: ski lifts, newspapers, ATMs � distribution of goods: retailing chains (food
stores, pharmacies, book stores, pubs)
• Horizontal foreclosure: bundling, tying - complement products with one firm having (near)
monopoly in one of the markets - Microsoft
� Windows/internet browser � Windows/media player
Tore Nilssen – Strategic Competition – Theme 9 – Slide 8
The Chicago School • There’s only one monopoly profit to be had. • Vertical integration and vertical foreclosure cannot be
harmful. • If there is a problem, it is that there is no competition
upstream. The foreclosure doctrine The upstream firm does indeed have incentives to favour one downstream firm, such as a downstream subsidiary.
Upstream monopolist
Downstream subsidiary
Downstream competitor
Tore Nilssen – Strategic Competition – Theme 9 – Slide 9
A reconciliation: the role of commitment • Having contracted with one downstream firm, the
upstream firm has incentives to contract further with other downstream firms, even though these firms in turn will compete with the first firm and decrease its profit.
• The first downstream firm realizes this and is less willing
to sign a contract. This reduces the upstream firm’s profit.
• The upstream firm will be looking for ways to get around
this problem. → Vertical foreclosure • Analogue: The durable-good monopolist. (Ronald
Coase) Model
U
D1 D2
Consumers p = P(q)
Tore Nilssen – Strategic Competition – Theme 9 – Slide 10
Timing Stage 1: Firm U offers firms D1 and D2 tariffs T1(⋅) and T2(⋅) for purchase of the intermediary good. Each Di then orders a quantity qi and pays Ti(qi). Stage 2: Firms D1 and D2 transform intermediate good into final good and sell at price p = P(q1 + q2). Define: Qm = arg maxq {[ P(q) – c)]q}
pm = P(Qm), πm = (pm – c)Qm
Observable contracts Firm U offers (qi, Ti) = (Qm/2, pmQm/2) to each downstream firm. They both accept and sell in total monopoly quantity at monopoly price. No rationale for foreclosure. But can firm U commit to these contracts? • If U and D2 agree on (q2, T2) = (Qm/2, pmQm/2), then
firms U and D1 would want to sign a contract that maximizes their joint profit given the U/D2 contract, with a quantity q1 given by:
q1 = arg maxq {[ P(Qm/2 + q) – c)]q} > Qm/2.
• Anticipating this, firm D2 would turn down the (Qm/2, pmQm/2) offer.
Tore Nilssen – Strategic Competition – Theme 9 – Slide 11
Secret contracts Passive beliefs: If a firm receives an unexpected offer, it does not revise its beliefs about the offer made to its rival. Consider a candidate equilibrium in which firm Dj is offered a quantity qj. Whatever firm Di is offered, it still believes that firm Dj is offered qj. Firm U offers firm Di a quantity qi so that the joint profit for U/Di is maximized, given the offer of qj to firm Dj: qi = arg maxq {[ P(q + qj) – c]q} This is the same problem as the one facing a Cournot duopolist. q1 = q2 = qC – the Cournot quantity The profit of the upstream firm: πU = 2πC < πm • The upstream firm suffers from its inability to commit. • The problem becomes more severe the larger the number
of downstream firms. • The more competitive the downstream industry, the more
interested is the upstream bottleneck owner in foreclosure in order to retain profit.
Tore Nilssen – Strategic Competition – Theme 9 – Slide 12
Why does the upstream firm foreclose access? Not in order to extend its market power to the downstream market, but rather in order to re-establish the market power lost because of its inability to commit. Downward integration Firm U buys one of the downstream firms. It credibly offers the monopoly quantity Qm to its own affiliate and nothing to the other. Bypass: Sometimes, there is an alternative supplier available to the non-integrated firm, so that the foreclosing firm can be bypassed. Still, if the alternative supplier is less efficient – for example, has higher production costs c > c – foreclosure with bypass is inefficient. Exclusive dealing • By entering an exclusive-dealing contract with D1, firm
U commits itself not to supply to D2. • A substitute for vertical integration.
Tore Nilssen – Strategic Competition – Theme 10 – Slide 1
Auctions Auction:
• One seller and a small number of potential buyers
The mirror image – Contract auction / Procurement auction:
• One buyer and a small number of potential sellers. • The buyer decides on the purchasing procedure,
potential sellers bid their prices. When are auctions used? • A unique object
- well defined? indivisible? • Uncertainty about who should get the object / the
contract • Uncertainty about the object’s value / the project costs • Commitment to selling / buying procedure
Tore Nilssen – Strategic Competition – Theme 10 – Slide 2
Alternatives to auctions Market
- decides who gets the object / project - but how to determine the price?
Bargaining
- determines the price - but how to determine who is the counterpart?
Handing out for free
- beauty contest - lobbying costs
Two concerns with an auction • For society - efficiency: Is the object bought by the
bidder with the highest willingness to pay? • For the seller: Is the price the highest possible? Several auction procedures How are these questions affected by the procedure chosen?
Tore Nilssen – Strategic Competition – Theme 10 – Slide 3
Various kinds of auctions • Sealed bids vs. open bids • Open bids
- Ascending bids – English auction � bidders submit higher and higher bids until
only one bidder remains � art, collectibles
- Descending bids – Dutch auction � seller starts with a high price and cries out
lower and lower prices until a bidder accepts � flowers (Netherlands), fish (Israel), tobacco
(Canada) • Sealed bids
- First price:
� The bidder with the highest bid wins and pays his bid.
� real estate, government procurement
- Second price: � The bidder with the highest bid wins and pays
an amount equal to the second highest bid. � Vickrey auction [Vickrey, J Finance 1961]
- William Vickrey, Nobel laureate 1996
� stamps etc. [Lucking-Reiley, J Econ Perspectives 2000]
Tore Nilssen – Strategic Competition – Theme 10 – Slide 4
Basic model • Bidders are risk neutral • Bidders’ valuations are different but independent • Each bidder knows only his own valuation • Seller doesn’t know any bidder’s valuation • No observable differences among the bidders • Reservation price?
Tore Nilssen – Strategic Competition – Theme 10 – Slide 5
Bidder behaviour (i) English auction
- continuing bidding is profitable as long as own valuation > current high bid
- this strategy is independent of what other bidders do (dominant strategy)
- the winner is the one with highest valuation → efficiency
- price is (just above) second highest evaluation
Tore Nilssen – Strategic Competition – Theme 10 – Slide 6
(ii) Sealed-bid second-price auction bidder B’s valuation = v bidder B’s bid = b largest bid from others = a • With a valuation of v, what should be bidder B’s bid, b? Distinguish between two cases: a > v: B’s decision does not matter a < v: B wins if b > a, and earns (v – a) • Bidding b < v reduces B’s chances to win but does not
affect what he has to pay if he wins. • Optimum bid: b = v
(dominant strategy) • The winner is the one with highest valuation
→ Efficiency • The price equals second-highest valuation • English auction and sealed-bid second-price auction are
equivalent with respect to winner and price. • Contract auction:
- winner is the one with lowest cost - price equals second-lowest cost
• Calculating the bid is easy
Tore Nilssen – Strategic Competition – Theme 10 – Slide 7
(iii) Sealed-bid first-price auction • Bidder trades off two concerns:
Bidding b < v - reduces his chances to win; not good. - reduces the price he has to pay if he wins; good.
• This trade-off makes the optimum bid lower than v. • The bidder knows that other bidders think the same way:
All bidders bid below their valuation. This makes the optimum bid even lower.
• This also holds for (iv) Dutch auction • The winner is the one with the highest valuation • The price equals highest bid, which is lower than highest
valuation • Expected price = Expected second-highest valuation • Calculating bid is difficult
Tore Nilssen – Strategic Competition – Theme 10 – Slide 8
Equilibrium bid – sealed-bid first-price auction n bidders, vi ∈ [vl, vh], i ∈ {1, …, n} cumulative distribution function: F(vi), i ∈ {1, …, n} Let’s focus on a symmetric equilibrium. Bidders are not identical, since valuations differ. But there are no observable differences, so their valuations are all drawn from the same cdf. In a symmetric equilibrium, there exists some function B(v), which is the same for all players, so that if one’s valuation is v, the equilibrium bid is B(v). Consider bidder i. He does not know the other bidders’ vs but believes that their bids depend on their valuations according to the function B(v). Assume: B’ > 0. ⇒ A bid of b implies a valuation equal to B-1(b). The probability that i’s bid bi is the winning bid =
[F(B-1(bi))]n – 1
Bidder i’s expected profit: πi = [vi – bi][F(B-1(bi))]
n – 1
Tore Nilssen – Strategic Competition – Theme 10 – Slide 9
Optimum bid satisfies: 0=∂∂
i
i
b
π
=∂∂=
∂∂+
∂∂=⇒
i
i
i
i
i
i
i
i
i
i
vdv
db
bvdv
d ππππ [F(B-1(bi))]
n – 1
In a symmetric equilibrium: bi = B(vi), ∀ i. ⇒ vi = B-1(bi)
In equilibrium, bidders’ beliefs about each other’s valuations are correct.
( )[ ] 1−=⇒ ni
i
i vFdv
dπ
Assume (reasonably): πi = 0 if vi = vl. ⇒ B(vl) = vl.
Integration:
( ) ( )[ ]∫−=
i
l
v
v
ni dxxFv 1π
Two expressions for bidder i’s profit – must be equal.
πi = [vi – bi][F(B-1(bi))]n – 1 = ( )[ ]∫
−i
l
v
v
n dxxF 1
( )( )[ ]( )[ ] 1
1
−
−∫
−==⇒ n
i
v
v
n
iiivF
dxxFvbvB
i
l
Tore Nilssen – Strategic Competition – Theme 10 – Slide 10
Common for all four kinds of auctions (in the base model):
• Efficiency: Object to the bidder with highest valuation (or lowest cost)
• Revenue equivalence: All four kinds give the seller the
same expected income. • An increase in the number of bidders increases the
expected price. - the more bidders, the higher is the expected second-
highest valuation. Difference among the auctions: • Bid more difficult to calculate in sealed-bid first-price
and Dutch auctions than in sealed-bid second-price and English auction.
Tore Nilssen – Strategic Competition – Theme 10 – Slide 11
Seller’s reservation price Revenue equivalence in the basic model: Seller indifferent between auction procedures. But what about a reservation price? A parallel situation: The monopolist’s problem A monopolist trades off two concerns: • wants to sell large quantities → low price • wants to earn a profit per unit sold → high price Optimum trade-off: Price above marginal cost Auction: Seller trades off the same two concerns: • wants to sell the object → low reservation price • wants to earn a profit if the object is sold
→ high reservation price The two highest valuations: v1, v2 Reservation price: r Three cases: (i) v1 > v2 > r: increasing r has no effect (ii) v1 > r > v2: increasing r increases the price (iii) r > v1 > v2: increasing r reduces the chances to sell
Tore Nilssen – Strategic Competition – Theme 10 – Slide 12
Optimum reservation price with 1 bidder Bid = r or nothing Seller’s own valuation: v0 Seller’s expected profit: π(r) = r[1 – F(r)] + v0F(r) FOC: [1 – F(r)] – rf(r) + v0f(r) = 0
⇒ ( )
( ) ( )rJrf
rFrv ≡−−= 1
0
i.e., marginal cost = marginal revenue ⇒ r = J-1(v0) Generally: If highest bidder has valuation v, his expected gain is
( )
( )vf
vF−1
so that the expected price in this case is
( )
( ) ( )vJvf
vFv =−− 1
The seller sells only if J(v) ≥ v0 for the highest bid ⇒ r = J-1(v0)
Effiency with a reservation price: • With a reservation price, the object may not be sold,
even if a bidder exists with v > v0. • Ex-ante efficiency vs. ex-post efficiency.
Tore Nilssen – Strategic Competition – Theme 10 – Slide 13
Some extensions (i) Observable differences among the bidders
Example: Public procurement – domestic vs. foreign firms. Suppose foreign firms are more cost effective than domestic ones.
• English auction and sealed-bid second-price auction are
still efficient. • Sealed-bid first-price auction no longer efficient: it is
possible to win the auction without having the lowest cost.
• It is optimum for the procurer to discriminate between
bidder groups, and one is no longer certain that the project is won by the lowest-cost bidder.
• In the example: It is optimum to discriminate in favour
of the domestic firms. This favouring - increases the chance of getting an inefficient
supplier, but also - lowers the bid from the efficient firms
Tore Nilssen – Strategic Competition – Theme 10 – Slide 14
(ii) Risk-averse bidders • In a sealed-bid first-price auction, risk-averse bidders bid
higher than risk-neutral ones. An increase in the bid (1) increases the chance of winning, and therefore
getting something (2) reduces what one earns in case of winning.
With risk aversion, (1) gets more important than (2) • Contract auction: Risk averse bidders bid more
aggressively than risk neutral bidders. • The seller gains more in a sealed-bid first-price auction
than in a sealed-bid second-price auction.
(iii) Correlated valuations • Extreme case: identical valuations. Bidders do not know
the object’s true value but have access to different pieces of information about this value. No bidder knows what other bidders know.
• More common in auctions than in contract auctions?
Auctions: - buying for resale - exclusive rights Contract auction - pioneering projects with great cost uncertainty for all potential suppliers
Tore Nilssen – Strategic Competition – Theme 10 – Slide 15
• “Winner’s curse”
- Bidders base bids in a sealed-bid auction on estimates. The bidder with the most optimistic estimate wins.
- If you win, then you will wish to revise your estimate: The winner is the most optimistic one.
- But this is taken into consideration in the bids: Bids are even lower because of the “winner’s curse”.
• In an English auction, bidders learn from each other
during the bidding process. This reduces the winner’s-curse problem.
- With correlated values, an English auction is preferred by the seller to the other kinds.
• Asymmetric information
- one bidder knows the object’s true value - US offshore oil and gas lease auctions
- Porter, Econometrica 1995
Tore Nilssen – Strategic Competition – Theme 10 – Slide 16
Other issues • Collusion
- second-price auction better for sustaining collusion among bidders than first-price auction
- open bids better than closed bids - contract auctions: Norsk Standard
• divisible objects
- securities, quotas • combined bids
- petroleum: price on exploration right + production fee
- vague projects: price + content • entry costs, number of bidders, participation fee • auctioning incentive contracts • competition for a market vs. competition in a market
Tore Nilssen – Strategic Competition – Theme 10 – Slide 17
Efficiency of auctions • Which auction procedure to use?
- revenue equivalence - easily calculated bids
→ sealed-bid second-price auction But: risk aversion? correlated values? • Which objects are sold most effectively in an auction?
- unique object - uncertainty about willingness to pay:
how large? who? • Does price affect efficiency?
- one unit – no quantity effects from price change - divisible objects (quotas, securities): quantity
effects Repeated auctions
- Less aggressive bidding today in order not to reveal one’s high valuation before future auctions (the ”ratchet” effect)
- better to have large projects? negotiating renewal with current supplier?
- Capacity constraints: The winner of a contract today may not have capacity to participate in the next round.