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Microeconomics - Introduction Economics involves the choices people make when matching their limitless needs and wants with a scarcity of resources. The word "economics" is derived from the Greek words "oikos", which means house, and "nomos", which means manager. So the term originally referred to management of the household. Today, the term has been broadened to refer to firms and all of society. Another way of looking at economics is to consider the field as a set of tools for analyzing people and groups and the choices that they make. Accountants are trained to render an account of financial activity for a company. Lawyers are trained into a certain mode of thinking so as to resolve issues in a legal framework. Similarly, economists are trained to use a set of tools and principles to analyze why individuals, firms, governments and other groups behave as they do. Models Economists often use models, which are representations of what the economist wishes to analyze. If, for example, an economist wishes to analyze the behavior of a labor union, the economist will not try to include every possible aspect and piece of data about labor unions in his or her model. Important factors will be focused on, such as wages, benefits, alternative jobs, etc. Hopefully the economist's model will include all of the important variables and will give little or no weight to less critical variables. Most economic analyses include the phrase "everything else is remaining the same", so attention can be focused on the variables specified by the model. Of course, this assumption is rarely true in real life. If one were trying to analyze federal deficits and interest rates, for example, there would be plenty of change during the time period analyzed. The CFA Level I Exam The economics portion of the CFA Level I exam touches on a

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Page 1: Microeconomics Investopedia

Microeconomics - Introduction

Economics involves the choices people make when matching their limitless needs and wants with a scarcity of resources. The word "economics" is derived from the Greek words "oikos", which means house, and "nomos", which means manager. So the term originally referred to management of the household. Today, the term has been broadened to refer to firms and all of society.

Another way of looking at economics is to consider the field as a set of tools for analyzing people and groups and the choices that they make. Accountants are trained to render an account of financial activity for a company. Lawyers are trained into a certain mode of thinking so as to resolve issues in a legal framework. Similarly, economists are trained to use a set of tools and principles to analyze why individuals, firms, governments and other groups behave as they do.

ModelsEconomists often use models, which are representations of what the economist wishes to analyze. If, for example, an economist wishes to analyze the behavior of a labor union, the economist will not try to include every possible aspect and piece of data about labor unions in his or her model. Important factors will be focused on, such as wages, benefits, alternative jobs, etc. Hopefully the economist's model will include all of the important variables and will give little or no weight to less critical variables.

Most economic analyses include the phrase "everything else is remaining the same", so attention can be focused on the variables specified by the model. Of course, this assumption is rarely true in real life. If one were trying to analyze federal deficits and interest rates, for example, there would be plenty of change during the time period analyzed.

The CFA Level I ExamThe economics portion of the CFA Level I exam touches on a wide range of economic theory. The material covered would normally be taught in senior (or graduate level) microeconomic, macroeconomic, money and banking, and international trade courses. You will need to understand all of the material presented here in order to successfully answer all of the questions given. There will be a few questions that require the solution of equations, particularly with regards to foreign exchange.

This section focuses on preliminary economic concepts you should know for your upcoming exam. Note that your upcoming CFA Level 1 exam will not test directly on these basic concepts, but CFA Institute notes that you should have a basic understanding of these topics to ensure success on the more challenging topics that lie ahead.

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Microeconomics - Supply and Demand

What is Microeconomics?Microeconomics is the branch of economics which looks at choices made by narrowly defined units, such as individual buyers/consumers, and firms that produce goods.

Two of the most important principles used by economists are the Law of Supply and the Law of Demand:

Law of SupplyThe law of supply says that, all other things remaining equal, as the price of a good increases (decreases), the quantity of that good supplied will increase (decrease).

Law of DemandThe law of demand states that, all other things remaining equal, as the price of a good increases (decreases), the quantity of that good demanded will decrease (increase).

Economists often use graphs as a way to demonstrate what is being discussed. The laws of supply and demand can be represented by a simple graph such as the one below.

Figure 3.1: Law of Supply and Demand

In figure 3.1, we can see that at the price of $1, the suppliers are willing to provide one million widgets (Point A), while the quantity demanded will be much higher - eight million (Point B).

At a higher price, such as $5, suppliers will be willing to provide six million widgets (Point D), while the quantity demanded is only one million (Point E).

Finally, at the price of $3, the quantity demanded is equal the quantity supplied (Point C). This price is also referred to as the "market clearing" or equilibrium price because no suppliers are left with the desire to provide goods at that price and no buyers are left wishing to purchase the goods at that price either.

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Look Out!

Note that supply and demand curves depict a quantity supplied or a quantity demanded at a particular price, all other things remaining equal.

Change in Consumer PreferenceSuppose there was a significant change in consumer preferences. For example, consumers suddenly have an increased desire for corn. This change in taste may be due to a new health study touting the benefits of corn, alternative grains such as wheat may have gotten more expensive, or corn growers may have conducted an effective advertising campaign. Regardless of the reason, the increase in demand results in a greater quantity demanded at particular price levels. This is an example of a demand shift.

Figure 3.2: Shift in the Demand Curve

In the graph above D0 represents the original demand curve, while D1 shows the new demand curve. Note that at a particular price level, such as $4, the quantity demanded increases from three million to five million.

Suppose something happens where the quantity of a good supplied changes at many particular price levels. For example, technological changes might occur whereby computer memory manufacturers would be able to produce a particular type of memory at a lower cost. So for many price levels, the quantity suppliers are willing to provide will increase. This situation could be diagrammed as below:

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Figure 3.3: Shift of the Supply Curve

S0 represents the original supply curve, while S1 represents the new supply curve. At the price of $30 per 256MB chip, the quantity supplied will increase from three million to four million units per month.

Supply and Demand MovementsChanges in quantity demanded strictly as a function of price are referred to as movement along a demand curve. A shift of the entire demand curve is referred to as a change in demand; this could be due to any factor(s) that affects demand, other than price.

Changes in quantity supplied strictly as a function of price are referred to as movement along a supply curve. A shift of the entire supply curve is referred to as a change in supply; this could be due to any factor(s) that affects supply, other than price.

Demand Curve ShiftsSome of the factors that can cause a demand curve to shift include:

1. Change in income - If consumer incomes increase, we might reasonably expect that demand for some luxury goods will increase.

2. Change in preferences/tastes - If a product becomes more (less) liked, the quantity demanded will increase (decrease).

3. Change in prices of goods that are complimentary - If the price of gasoline goes up substantially, the demand curve for large SUV's should shift down.

4. Changes in prices of goods that are substitutes - If the price of pork increases (decreases), demand for beef would likely increase (decrease).

5. Advertising - An effective advertising campaign could increase the quantity demanded of a particular good. It could also decrease the demand for a competing good.

6. Expectations - If consumers expect a good to become more expensive or hard to get in the future, it could alter current demand

7. Shifts in market demographics - As segments of the population age or their composition changes, their demands also change. Because segments are not equally distributed – that is, there are not a consistent number of people in every age category – larger segments have a more noticeable impact on demand. The baby boomers are an excellent example of this.

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8. Distribution of income - For example, if the rich get richer, and the poor get poorer, demand for luxury goods could increase.

Supply Curve ShiftsFactors that would cause a shift in the supply curve include:

1. Cost - An increase in crude oil costs for a plastic manufacturer would shift the supply curve up and to the left. Changes in technology can dramatically decrease costs.

2. Government tax policy - Increases in business taxes will cause the supply curve to shift up and to the left. A government subsidy to producers will cause more supply to be available - the supply curve will shift down and to the right.

3. Weather/climate - Changes in weather and/or climate will especially influence agricultural product supply.

4. Prices of substitute products - If farmers can grow wheat instead of corn, and the price of wheat goes up, then the supply curve for corn will shift up and to the left as more farmers switch from corn to wheat.

5. Number of producers - As the number of firms/individuals producing a product increases, we would expect more supply to be available.

Short- and Long-Run Market EquilibriumIn the short run, market equilibrium is achieved when the quantity demanded is equal to quantity supplied and the market clears. The market is said to be cleared because there is no additional quantity supplied, or quantity demanded, at the market clearing price.

However, that particular market price may not lead to equilibrium in the long run. In the short run, producers do not have time to fully adjust to current market conditions. Some current producers may not be making a profit or covering all their costs at the current market price. Producers in that situation will consider leaving the industry, or at least will not allocate further capital to that industry. If producers are making profits, then we would expect more resources to be allocated to the industry such as the building of additional factories. In the long run, all factors of production can be varied.

Long-run equilibrium is something we expect the market to move towards over time. The process could take years. It actually may never be achieved because demand and supply curves are constantly shifting.

Suppose there is an increase in demand, as shown by the graph below.

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Figure 3.4: Effects of a Shift in Demand

D0 is the original demand curve, and D1 is the new demand curve. The market equilibrium price will increase from P0 to P1, at least in the short-run. The quantity will also increase from Q0 to Q1.

Over time, in a market economy, two forces will come into play:

1. Buyers will have an incentive to search for substitutes, thereby decreasing their purchase of the original good; this effect will tend to lower the quantity demanded and the market price

2. Suppliers will have an incentive to supply more of the good, and more resources will be allocated towards production of this good; this effect will tend to increase the quantity and lower the market price

Shortages and Surpluses and their Effect on Equilibrium PricesA "shortage" exists when the quantity demanded at the current price is greater than the quantity supplied. In the case of shortage, we would expect the market price to go up. In this case, less motivated buyers do not purchase the good and producers have a strong incentive to supply more at the higher market price. This process will continue until the quantity demanded is equal to the quantity supplied. A "surplus" exists when the quantity supplied is greater than the quantity demanded. In this case, we would expect the market price to go down. The lower market price entices more consumers into buying, but lower profits create an incentive for producers to reduce the quantity supplied.

Invisible Hand PrincipleMarket prices deliver information to producers on how to allocate capital and other resources. Prices tell producers about consumer needs and wants by showing them how much consumers are willing to pay for a particular good or service. Prices also inform consumers by sending signals about how much of a given product is available.

These market prices act as an "invisible hand" that pushes self-interested individuals toward the correct allocation of resources, benefitting both the individuals and society as a whole. No one person is consciously making these decisions.

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Microeconomics - Price Elasticity

Now that you have completed the basics, let us move onto the various learning outcomes on Microeconomics you should look to know for your upcoming exam.

Price ElasticityIn general, the elasticity of a particular variable is the percentage change in quantity demanded or supplied, divided by the percentage change in the variable of concern. This ratio is often called the elasticity coefficient.

Price elasticity is defined as the percentage change in quantity demanded divided by the percentage change in price.

The price elasticity of demand can be expressed as:

Formula 3.1

Example: Price ElasticityWhere Ep is the price elasticity coefficient, %ΔQ represents the percentage in quantity, and %ΔP represents the percentage in price. If the price of gasoline goes up by 50%, and the quantity demanded decreases by 20%, the price elasticity of gasoline would be:

Ep = %Δ Quantity = -20% = -0.4%Δ Price +50%

Typically, the negative sign is ignored and we would say that the price elasticity of gasoline is 0.4.

To calculate elasticity we must first have data for quantities purchased at different prices. Suppose that the price of a good goes from P0 to P1, and that we have data for the change in quantity demanded, which goes from Q0 to Q1. The calculation is typically made by dividing the actual change by the average(or midpoint) of the beginning and ending values. Suppose that the quantity demanded of a good goes from 10 to 14. The percentage change in quantity demanded could be expressed as:

(Q0 - Q1) = 4 = 0.3330.5(Q0 + Q1) 0.5(24)

That number would be multiplied by 100 to get the percentage change, which in this case would be 33.3%.

Similarly, the percentage change in price can be expressed as:

(P0 - P1) x 1000.5(P0 + P1)

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Look Out!Sometimes the denominator used for these percentage change calculations is simply the original value (P0 and Q0). Because the CFA text uses the midpoint method, unless the exam has instructions to the contrary, it would be safer to use the midpoint method.

The full elasticity calculation can be simplified by canceling out the 0.5 (one-half) and 100. The more simplified expression can be stated as:

Example:Suppose, to continue the example given above, that the change in quantity demanded for the good (10 to 14) was in response to a price decrease from $8 to $7. In that case, the elasticity would be expressed as:

(10 - 14) / (10 + 14) = -4 / 24 = -1/6 = -15 = -2.5(8 - 7) / (8 + 7) 1 / 15 1/15 6

Alternatively, the elasticity could have been calculated as: -4 divided by half of 24, which is equal to -0.333, over 1 divided by half of 15, which equals 0.1333.

So the elasticity would be -0.333 over 0.133 = - 2.5, the same answer as above.

The following definitions apply to calculations of price elasticity:

1) If Ep > 1, Demand is elastic. The percentage change in price will produce a greater percentage in quantity demanded. If the price goes up, then total revenues will go down. If the price goes down, then total revenues willincrease.

2) If Ep < 1, Demand is inelastic. The percentage change in price will produce a lower percentage in quantity demanded. If the price goes up, then total revenues will go up. If the price goes down, then total revenues will decrease. Put simply, these changes will be less drastic than if demand is elastic.

3) If Ep = 1, Demand has unitary elasticity. A percentage in price will produce the exact same percentage change in quantity. Therefore, changes in price will no have effect on total revenues.If demand is elastic for a product, then a small change in price will cause a large change in quantity demanded. If the demand for a product is inelastic, even a large change in price might cause little change in quantity demanded.

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Microeconomics - Elasticity of Demand

Determinants of price elasticity include:

Availability of substitutes - if substitutes are plentiful, then demand should be elastic. Relative percentage of expenditure - if an item takes up a considerable proportion of a

consumer's income, then demand should be elastic; if it takes up a very small amount, then demand should be expected to be inelastic.

Amount of time - consumers can make more adjustments to prices changes over time and, therefore, demand tends to be more elastic as time passes.

Necessities or luxuries - demand for necessities will tend to be inelastic, while demand for luxuries will tend to be elastic.

Cross Elasticity of DemandCross elasticity of demand relates the percentage change in quantity demanded of a good to the percentage change in price of a substitute or complementary good. Examples of complementary goods would include peanut butter and jelly, and large SUVs and gasoline. The cross elasticity of demand will be positive for a substitute, and negative for a complement; i.e. demand for a substitute (complement) will go up (down), if the price of the substitute (complement) goes up.

The following formula can be used to calculate cross-elasticity of demand:

Formula 3.2

Where: CEp is the cross-price elasticity coefficient,

%ΔQ represents the percentage change in quantity demanded, and

%ΔP represents the percentage change in price of the substitute or complement.

Income ElasticityIncome Elasticity is defined as the percentage change in quantity demanded divided by the percentage change in income. The calculations are similar to those for price elasticity, except that the denominator would include a change in income instead of a change in price.

Usually the amount of goods purchased will be positively correlated with income; if consumers' incomes go up (down), more (less) goods will be purchased. Any good with a positive income of elasticity of demand is said to be a normal good. Luxury goods have high income elasticity (greater than one). The proportionate amount of spending for those goods will go up as incomes increase.

The amount spent on some goods decrease as incomes goes up. Such goods are referred to as inferior goods. Examples of inferior goods include margarine (inferior to butter) and bus travel (inferior to owning a vehicle).

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Microeconomics - Elasticity of Supply

Supply elasticity is defined as the percentage change in quantity supplied divided by the percentage change in price. It is calculated as per the following formula:

Formula 3.3

The calculation of elasticity of supply is comparable to the calculation of elasticity of demand, except that the quantities used refer to quantities supplied instead of quantities demanded.

Factors that influence the elasticity of supply include the ability to switch to production of other goods, the ability to go out of business, the ability to use other resource inputs and the amount of time available to respond to a price change.

Over a short time period, firms may be able to increase output only slightly in response to an increase in prices. Over a longer period of time, the level of production can be adjusted greatly as production processes can be altered, additional workers can be hired, more plants can be built, etc. Therefore, elasticity of supply is expected to be greater over longer periods of time.

We would expect the supply elasticity of wheat to be very high as farmers can easily switch land that is used for wheat over to other crops such as corn and soybeans. On the other hand, an oil refinery cannot easily switch its production capacity over to another product, so low oil-refining margins do not reduce the quantity supplied by very much. Due to high capital costs, higher refining margins do not necessarily induce much greater supply. So the supply elasticity for oil refining is fairly low.

Microeconomics - Marginal Benefit and Marginal Cost

Within this section we will focus on determining the difference between marginal benefit and marginal cost, as well as how to calculate the efficient quantity.

Consumer ChoiceEconomic analysis generally assigns the following properties to consumers:

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Consumers make rational decisions. If two products are of equal benefit to a consumer, then he or she will choose the cheaper product. If two products are the same price, the consumer will choose the one that provides the higher benefit.

Limited income enforces choice. Consumers have to make choices as to what goods will be purchased or not purchased. Purchasing one item means that less funds are available to purchase other items.

Substitution of goods. Consumers can achieve satisfaction, which is generally referred to as utility, with many choices. The satisfaction and cost of a cheeseburger can be evaluated in comparison to other goods - such as hot dogs.

The Law of Diminishing Marginal Utility. This law refers to marginal utility, which describes the increase in satisfaction from consuming one additional unit of the good. The Law of Diminishing Marginal Utility states that as each additional unit of a good is consumed, the amount of marginal (incremental) utility will decrease.

Economists believe that consumers make decisions at the margin; i.e. should one more unit of the good be obtained or not? The consumer will compare the additional (marginal) utility to be achieved by consuming one more unit of the good, to the additional (marginal) utility that must be given up (buying power) in order to obtain the good. At any particular price, the consumer will continue to buy units of the good as long as the marginal benefit, as expressed by maximum willingness to pay, exceeds the price. The marginal benefit indicates, in dollar terms, what the consumer is willing to pay to acquire one more unit of the good; it can also be related to the height of an individual's demand curve. Another implication of the Law of Diminishing Marginal Utility is that the height of the demand curve will fall as more units of the good are consumed.

Another implication of marginal utility theory is that for consumers to maximize utility, the following relationship holds:

MUa = MUb = MUc = and so on...Pa Pb Pc

MU refers to marginal utility of the good, P represents the price of the good, and the subscripts indicate a particular good. The last unit of each good purchased will provide the same marginal utility per dollar spent on that good.

The term marginal cost refers to the opportunity cost associated with producing one more additional unit of a good. Opportunity cost is a critical concept to economics - it refers to the value of the highest value alternative opportunity. For example, in examining the marginal cost of producing one more bushel of wheat, that number could be expressed as the dollar value of corn or other goods that could be produced in lieu of more wheat.

Marginal benefit refers to what people are willing to give up in order to obtain one more unit of a good, while marginal cost refers to the value of what is given up in order to produce that additional unit. Additional units of a good should be produced as long as marginal benefit exceeds marginal cost. It would be inefficient to produce goods when the marginal benefit is less than the marginal cost. Therefore an efficient level of product is achieved when marginal benefit is equal to marginal cost.

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Consumer Surplus and Marginal BenefitConsumer surplus represents the difference between what a consumer is willing to pay and the actual price paid. If a consumer is willing to pay $5.00 for a gallon of gasoline, and the actual price is $3.00, then there is a consumer surplus of $2.00 with the purchase of that gallon of gasoline. The value to the consumer, or marginal benefit, is $5.00. Value is calculated by getting the maximum price that consumers are willing to pay.

We expect consumers to continue purchasing units of a good as long as the marginal benefit exceeds the price paid; i.e., as long as there is a consumer surplus to be achieved.

Microeconomics - Market Efficiency

Marginal (or Opportunity) Cost and the Minimum Supply PriceThe supply curve (see figure 3.3) represents the quantities of a particular good that producers are willing to supply at various price points. For any particular quantity, the height of the supply curve represents the minimum price that suppliers of a good must get in order to supply the additional unit. That minimum supply price must cover the increase in total costs, or marginal cost, of producing the additional unit. The opportunity cost represents the value of other goods that may have been produced with the resources used. Producers must receive a price at least equal to their opportunity cost.

Producer surplus is defined as the difference between what a producer actually receives (which will be the market price) for a product and the producer's minimum supply price (marginal cost) for that product. If a producer is willing to provide a unit of a good for $3.00, and actually gets $4.00, then the producer would have $1.00 of producer surplus.

Consumer Surplus, Producer surplus, and Equilibrium.We expect consumers to keep consuming additional units of a good until the marginal benefit no longer exceeds the price, or there is no longer an increase in consumer surplus. Producers will continue to provide additional units of a good up to the point where the market price no longer exceeds their minimum supply price.

The marginal benefit for all people in a society can be described as the marginal social benefit. Similarly the marginal costs for all producers in a society of a good can be described as the marginal social cost. At market equilibrium, the marginal social benefit of consuming an additional unit of a good is just equal to the marginal social cost of producing the additional unit.

In the figure 3.5 below, the triangle defined by the points P2PmQm represents consumer surplus, while the triangle defined by points P1PmQm represents producer surplus.

Figure 3.5: Consumer and Producer Surplus

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How Resources Move Toward Their Most Efficient AllocationIn economics, a market is efficient if the maximum amount of goods and services are being produced with a given level of resources, and if no additional output is possible without increasing the amount of inputs. Efficient markets ensure optimal resource utilization by allowing for price to motivate independent actors in the economy. If buyers and sellers are free to choose how to allocate resources, prices will direct resources towards those who value them most and can utilize them most effectively.

Suppose consumer preferences change so that good A is now more desired than good B. We would expect the price of good A to shift higher and the price of good B to shift lower. This in turn will induce the production of additional units of good A and the devotion of more input resources to good A, while similarly decreasing production of B and its associated input resources.

In the real world today we have seen higher oil prices stimulate more drilling for oil and more investment in oil substitutes. The wage rates of mainframe programmers in the United States has decreased over the last several years in comparison to the year 2000, as there less of a need for their services. The lower wage rates have induced more mainframe programmers to retrain themselves with other computer skills, or to leave the field.

Obstacles to achieving efficiency include:

· Price Ceilings/Floors - Sometimes governments impose price ceilings, which define a maximum price, or price floors, which define a minimum price. Effective price ceilings or floors prevent normal market equilibrium.

· Public Goods are goods available to everyone, even if they don't pay. Examples include police protection and public parks. One reason competitive markets don't produce the optimum amount of a public good is due to the "free-rider" problem: those who don't pay get a "free ride" with regards to getting the benefit.

· Externalities reflect costs and benefits not borne by the person or firm making the economic decision, which are imposed on or granted to others. Runoff from large cattle feedlots can damage nearby farms, and this potential cost may not be considered by feedlots when they look at their supply curve. A landowner who chooses not to develop her land may benefit several other homes for purposes of flood control. The benefit to others may not be taken into account when deciding to develop the land.

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· Taxes lead to lower quantities produced, higher prices for buyers and lower effective prices for sellers.

· Subsidies increase the quantity produced, lower prices for buyers and increase seller prices.

· Quotas limit the quantity that can be produced.

· High transaction costs reduce the price that customers are willing to pay and increase supplier costs, leading to an equilibrium quantity that is lower than either party would desire absent the higher costs.

· Asynchronous information creates a perceived cost for buyers and sellers if they cannot adequately evaluate a proposed transaction. Drug companies can charge premium prices for pharmaceuticals due in part to the established evidence that the drug works. Auto makers entering new markets often have to offer lower prices and/or better warranties because customers do not have sufficient information about the new brands.

· Discrimination deprives market participants of the ability to conduct business at prices that otherwise be acceptable to them. Businesses that discriminate against certain types of job-seekers may have to pay more for labor, while customers that discriminate against a business may have to pay more for goods.

· A monopoly means that only one firm can provide a certain good or service. A monopolist will charge a higher price and produce a lower quantity in comparison to a competitive market.

With the exception of the above-mentioned obstacles, a competitive market will use resources efficiently. Goods are produced up to the point where the marginal benefit is equal to the marginal cost, and the sum of consumer and producer surplus is maximized.

Although price is the dominant means of allocating resources in a market economy, it is not the only way for markets to allocate resources. A command economy relies upon a central planning authority to allocate resources. Markets can also allocate resources by majority rule (citizens vote on the desired allocation of resources), lottery, or force and theft.

The Fairness Principle, Utilitarianism, and the Symmetry PrincipleEconomists often like to examine the "fairness" of a situation or economic system. Ideas about fairness can be lumped into one of two categories:

· "Results" must be fair.· "Rules" must be fair.

Utilitarianism, which is a moral philosophy developed in 18th and 19th century Great Britain, posits that an action is correct if it increases overall happiness for the performer of the act and those affected by the act. Utilitarians argued that income should be transferred from the rich to the poor until complete equality was achieved.

One problem with utilitarianism is the tradeoff between fairness and inefficiency. An effort to transfer wealth by heavily taxing rich people will decrease incentives for people to save

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money or work hard. This can lead to inefficient uses of capital and labor. Another source of inefficiency is the administrative cost of transferring money from the rich to the poor.

The symmetry principle is based on the intuitive principle that people in similar situations should be treated the same. From an economic perspective, we would like to achieve equality of opportunity. The symmetry principle adheres to the viewpoint that "rules" must be fair.

Microeconomics - Price Ceilings and Floors

Price CeilingsIf the price ceiling is above the market price, then there is no direct effect. If the price ceiling is set below the market price, then a "shortage" is created; the quantity demanded will exceed the quantity supplied. The shortage may be resolved in many ways. One way is "queuing"; people have to wait in line for the product, and only those willing to wait in line for the product will actually get it. Sellers might provide the product only to family and friends, or those willing to pay extra "under the table". Another effect may be that sellers will lower the quality of the good sold. "Black markets" tend to be created by price ceilings.

Figure 3.6: Effect of Price Ceilings

Figure 3.6 illustrates the shortage that occurs when a price ceiling is imposed on suppliers. Consumers demand QD while Suppliers are only willing to supply QS. If the price ceiling is set above the equilibrium, consumers would demand a smaller quantity than suppliers are producing.

Economic Efficiency: Black Vs. Legal MarketsLegal systems provide various benefits to economic systems.

Economic efficiency may be said to occur when an action creates more benefits than costs. Legal systems help economic systems become more efficient by reducing risks to economics participants. Risk represents a cost that must be compensated for by higher charges.

One risk reduced by government regulation is theft. Government protects the property rights of owners so that they can benefit from the assets they own and use them in an efficient, economic manner. Participants in a "black market system" face a high risk of theft in their transactions as well as exposure to other forms of violence.

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Governments often also provide a regulatory framework for the safety of products. In a market operating within a legal system, purchasers of drugs have a reasonable expectation about the quality of the drugs and the expected benefits of the drugs. Participants in a black market for drugs will have incomplete information about the quality of drugs purchased and, therefore, appropriate decisions are more difficult to make.

Price FloorsWhen a "price floor" is set, a certain minimum amount must be paid for a good or service. If the price floor is below a market price, no direct effect occurs. If the market price is lower than the price floor, then a surplus will be generated. Minimum wage laws are good examples of price floors. In many states, the U.S. minimum wage law has no effect, as market wage rates for low-skilled workers are above the U.S. minimum wage rate. In states where the minimum wage is above the market wage rate, the law will increase unemployment for low-skilled workers. Although some low-skilled workers will get higher pay, others will lose their jobs.

Microeconomics - Effect of Taxes on Supply and Demand

Taxes reduce both demand and supply, and drive market equilibrium to a price that is higher than without the tax and a quantity that is lower than without the tax.

Actual and Statutory Incidence of TaxTax authorities usually require either the buyer or the seller to be legally responsible for payment of the tax. Tax incidence is the way in which the burden of a tax is shared among the market participants ("who bears the cost?"). Taxes will typically constitute a greater burden for whichever party has a more inelastic curve – e.g., if supply is inelastic and demand is elastic, the burden will be greater on the producers.

Suppose that a state government imposes a tax upon milk producers of $1 per gallon.

Figure 3.7: Incidence of Tax

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Figure 3.7 shows the original price for milk was $2 per gallon. After imposition of the tax, the supply curves shift up and to the left. Consumers pay $2.60 per gallon. Sellers receive $1.60 per gallon after paying the tax. So sixty cents of the tax is actually paid by consumers, while forty cents is paid by the milk producers.

The triangle ABC above represents the deadweight loss due to taxation, which occurs because now there are fewer mutually beneficial exchanges between buyers and sellers. Deadweight loss stems from foregone economic activity and is a loss that does not lead to an offsetting gain for other market participants; it is a permanent decrease to consumer and/or producer surplus.

Elasticity of Supply and Demand and the Incidence of TaxIf buyers have many alternatives to a good with a new tax, they will tend to respond to a rise in price by buying other things and will, therefore, not accept a much higher price. If sellers easily can switch to producing other goods, or if they will respond to even a small reduction in payments by going out of business, then they will not accept a much lower price. The incidence of the tax will tend to fall on the side of the market that has the least attractive alternatives and, therefore, has a lower elasticity.

Cigarettes are one example where buyers have relatively few options; we would therefore expect the primary burden of cigarette taxes to fall upon the buyers.

A subsidy shifts either the demand or supply curve to the right, depending upon whether the buyer or seller receives the subsidy. If it is the buyer receiving the subsidy, the demand curve shifts right, leading to an increase in the quantity demanded and the equilibrium price. If the seller receives the subsidy, the supply curve shifts right and the quantity demanded will increase, while the equilibrium price decreases.

A quota limits the amounts of a good that can be produced. If the quota is greater than what would be produced under normal market conditions, then it will have no effect. If the amount is less, than the market equilibrium that is achieved will be at a higher price than what would occur without the quota, as consumers will be willing to pay more.

Making a good or service illegally impacts demand, supply and market equilibrium by imposing a cost (prosecution and punishment) on the buyer or seller (or both) of the good/service. Quantities of illegal goods will always be less than if they were legal, but the impact on price is determined by whether the buyer or seller (or both) is punished. If the only the buyer is penalized, the equilibrium price will be lower; the risk of punishment is regarded by buyers as a cost, and reduces the price they will pay to the seller. If the seller is penalized, the equilibrium price will be higher as the cost of punishment is factored into the seller's cost. Prices will remain relatively unchanged if the risk and cost of punishment is shared equally.

Microeconomics - Opportunity Costs

Explicit CostsExplicit costs reflect monetary payments made to resource owners. Examples include wages, lease payments and interest payments.

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Implicit CostsImplicit costs are those associated with resources used by the firm, but with no direct monetary payment. For example, there may not be an explicit monetary payment associated with the work efforts of a sole proprietor; however, there is an implicit cost associated with those work efforts as the sole proprietor could earn wages elsewhere. For a firm's capital, there is an implicit cost involved as the firm could be getting interest or earning a rate of return elsewhere. The implicit cost associated with the highest-valued alternative opportunity is referred to as the opportunity cost.

On the reverse side, particularly for an individual, there may be forms of implicit ("psychic") revenues; for example, a person may particularly enjoy "being his own boss".

Economic ProfitEconomic profit is equal to total revenues less both implicit and explicit costs. For a firm to stay in business, both implicit and explicit costs must be covered. If firms are receiving a negative economic profit in a market, they will leave that market. A normal profitrate exactly covers wage costs and the competitive rate of return on capital.

Accounting ProfitsAccounting profits are generally higher than economic profits, as they omit certain costs, such as the value of owner-provided labor and the firm's equity capital.

When calculating "economic profit", explicit and opportunity costs are taken into account.

Example:Suppose someone owns and runs a candy store that grosses $20,000 per month and has operating expenses of $14,000 per month. The store owner particularly enjoys socializing with the customers; this aspect of the business provides a comfort to the owner which is worth $2,000 a month to her. The owner could receive $3,000 a month in interest with the capital that is tied up in the store's inventory. She could earn $5,000 a month at a different job.

An income statement would show an accounting profit of $6,000 a month:

Explicit Revenues $20,000

Explicit Costs $14,000----------Accounting Profit $ 6,000

Answer:The economic profit, which should determine the economic decision, would be calculated as follows:

Explicit Revenues $20,000

Implicit Revenue(value of socialization) $ 2,000- - - - - -Economic Revenues $22,000

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Explicit Costs $14,000

Implicit Costs:Value of owner's labor $5,000Required rate of return oninventory investment $3,000- - - - - -Economic Profit ($2,000)

From an economic viewpoint, keeping the candy store open does not make sense. The implicit value of enjoying being with the customers is not of sufficient value in comparison to the fact that the store owner could make more money by working elsewhere and employing the capital elsewhere.

Microeconomics - Achieving Economic & Technological Efficiency

Firm ConstraintsConstraints on a firm include:

Information - firms will not have complete information regarding strategies of competitors, ethics of their workers, customer buying plans, forthcoming technologies and many other factors that affect firm profitability. Acquiring relevant information can be costly, so benefits and costs of acquiring information must be weighed.

Market - prices firms charge will be impacted by the offerings of other firms. Firms are in competition with other firms for resources such as employees and raw materials. Market constraints limit what firms can charge and enforce pricing on the input side.

Technology - economists view technology as the methods and processes that firms use to produce goods and/or services. There is a "technology" associated with any business, and the set of available technologies will limit what a firm can do and impact its profit.

Technological vs. Economic EfficiencyTechnological efficiency relates quantities of inputs to the quantity of output, while economic efficiency relates the dollar value of inputs to the dollar value of output. A firm would be operating with technological efficiency when it produces a certain level of output with the least amount of input. Economic efficiency would be achieved when a certain level of output is produced with the lowest cost of inputs.

Suppose there are two available methods to produce widgets, one that is highly automated with industrial robots, and a mostly manual one that requires significantly more workers. The automated method costs $50,000 per month to produce 1,000 widgets over a monthly period, using three robots and one worker. The manual method costs $40,000 per month to produce 1,000 widgets over the same time period, with 10 workers that have a minimal amount of tools. We can't say that either method is technologically inefficient - the automated method requires fewer workers, while the manual method requires less capital for the same quantity

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of output. However, we can say that the manual method is economically efficient, since it produces 1,000 widgets at the lower cost.

Ways to Organize ProductionThere are two broadly defined methods of organizing production. A command system utilizes a hierarchical organization whereby commands flow down from the top of the organization. Armies typically are organized by this method. An incentive system tries to provide market-like incentives to each layer of the organization. Sales organizations predominantly use incentive systems. Incentives also can be provided to personnel, such as assembly line workers, by relating pay to certain production targets.

The Principal-Agent ProblemThe principal-agent problem is an example of incomplete and asymmetric information. Principal-agent problems occur when the principal (buyer) has less information than the agent (supplier). For example, a patient at a hospital has much less information about the medical treatments being conducted than the doctors. The patient would prefer to have the illness resolved at the lowest possible cost to him. The doctors may be facing pressures or may be influenced by incentives that are not in the best interests of the patient. It is difficult for the patient to judge the quality of his or her own treatment.

Owners (shareholders) of firms face similar problems. The owner (principal) compensates an agent (an employee) to perform acts that are useful to the principal, costly (or otherwise undesirable) to the agent, and where performance is costly or difficult to observe. Because of the difficulty/cost of observing the work, the principal finds it difficult to assess the agent's competence and achievements and adjusting compensation accordingly. Likewise, there is an inherent conflict of interest at work – the principal seeks to gain maximum output for minimum compensation, while the agent seeks to maximize compensation and minimize output.

A firm can reduce principal-agent problems by giving the agent an ownership stake in the enterprise, incentive compensation and/or a long-term employment contract. These serve to give the agent a vested interest in the overall health of the enterprise and align the interests of the principal and the agent.

Types of Business Firms:

ProprietorshipsProprietorships are businesses owned by a single individual (or sometimes a family). Risks and rewards for the business are the responsibility of that one individual. Note that the sole proprietor is legally responsible for the debts of the business.

PartnershipsPartnerships are businesses that have two or more people acting as co-owners of the business. Agreements are made beforehand as to how to share the risks and rewards. As with proprietorships, owners are personally responsible for all debts associated with the business. Law firms and accounting firms are organized often as partnerships.

CorporationsCorporations are businesses that have been granted a charter so that they are recognized as separate legal entities. Individuals in a corporation are not subject to the liabilities of the firm;

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the most that they can lose is the amount they invested. Taxes are paid, assets are acquired and contracts are entered into n the name of the corporation. Corporations generally have easier access to capital than proprietorships or partnerships.

Major factors promoting cost efficiency and customer service within the corporate world include:

1. The threat of takeover - Inefficient corporate management can attract the interest of outsiders, who will try to take over of the corporation with the intent of running the corporation more efficiently, so as to increase shareholder value. The takeover company most likely would remove the current management. The threat of such a takeover gives management an incentive to serve the interests of corporate shareholders.

2.Competition for capital and customers - Poor management will tend to drive the price of a company's stock down, which will tend to make raising more capital difficult. An efficient and/or innovative management will tend to cause the price of a company's stock to go up, which will make raising additional capital easier. The corporation's products must be competitive, in terms of both price and quality, in order to attract customers. The production of inferior goods will tend to drive customers away, which will decrease corporate revenues. Therefore, competitive forces tend to limit the ability of management to serve their own needs in lieu of stockholder and customer needs.

3.Management compensation - Compensation can be set up so that management incentives are in line with those of the corporation. For example, a significant amount of executive compensation can be in the form of stock options, which are of value only when a certain stock price is met.

Microeconomics - Types of Markets & Concentration Measures

Price Taker MarketsA purely competitive (price taker) market exists when the following conditions occur:

· Low entry and exit barriers - there are no restraints on firms entering or exiting the market·Homogeneity of products - buyers can purchase the good from any seller and receive the same good·Perfect knowledge about product quality, price and cost·No single buyer or seller is large enough to influence the market price

Sellers must take the existing market price and they will adjust the quantity of their products so as to maximize profit at the market price. Because sellers must take the current market price, a purely competitive market also is called a "price takers" market.

Price-Searcher MarketsPrice-searcher markets are characterized by:

1.Barriers to Entry

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2.Firms in the Markets that have Downward-Sloping Demand Curves

While perfectly competitive markets have a homogeneity of goods, price-searcher markets have a differentiation of goods. The differentiation could be in the form of location, taste, packaging, design, quality and many other factors. Some textbooks use the phrase "monopolistic competition" to describe markets where each firm has something unique about its product while facing significant competition. A good example would be a gas station. Although there are many competing gas stations, an individual gas station is the only one at its particular location and, therefore, to some degree it has a monopoly or is a sole seller. The CFA text prefers the term "competitive price searcher".

Firms in a price-searcher market with low barriers to entry have some flexibility to raise prices, as they will not lose all their customers if they do so. For example, if Valvoline raises the price of its motor oil, some people will be willing to pay the price for the motor oil they prefer. However, rival firms such as Pennzoil or Castrol also provide similar motor oils. As Valvoline raises its prices, many customers will switch to rival suppliers. The demand curve faced by firms in competitive price search markets, such as motor oil, will be highly elastic.

Firms in price-searcher markets with low barriers to entry face competition from existing suppliers and potential new entrants. If economic profits are being made in the market, then more firms will be expected to enter the market. Price searchers can set their prices, but the actual quantities sold will depend upon market forces.

MonopolyMonopoly refers to a "single seller". The single seller will have a market with no well-defined substitute. The monopolist does not need to worry about the reactions of other firms. Utility companies are often monopolists in particular markets.

ConcentrationConcentration within an industry refers to the degree to which a small number of firms provide a major portion of the industry's total production. If concentration is low, then the industry is considered to be competitive. If the concentration is high, then the industry will be viewed as oligopolistic or monopolistic. Government agencies such as the U.S. Department of Justice examine concentration within an industry when deciding to approve potential mergers between industry firms.

The most common measure of concentration is the four-firm concentration ratio, which is defined as the percentage of the industry's output sold by the four largest firms. An industry with a four-firm concentration ratio of forty percent is generally considered to be competitive.

The Herfindahl-Hirschman Index (HHI) calculates concentration ratios by squaring the market share of the fifty largest firms in an industry. The formula can be expressed as follows:

Formula 3.4

HHI = s12 + s2

2 + s32 + ... + sn

2

(where sn is the market share of the ith firm).

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A monopoly would have the largest possible value - 1002 = 10000. The HHI for a highly fragmented industry would be close to zero. The Justice Department generally considers an industry with an HHI above 1800 to be highly concentrated.

Limitations of Concentration MeasuresConcentration ratios have some of the following limitations:

· Foreign production – concentration ratios often fail to fully incorporate the revenue from foreign companies, thus overestimating the concentration of a domestic industry and underestimating the impact of foreign goods on competition.

· Ease of entry – an industry may have relatively few participants, but low barriers to entry. In such cases, a concentration ratio will overstate the power of current suppliers.

· Elasticity of demand – concentration ratios do not factor in the elasticity of demand and the availability of substitutes. Many highly-concentrated industries (metals, airlines, et al) are constrained by the availability and cost of substitute products and services.

· Imprecise definitions – a narrowly-defined industry will appear to be more concentrated than a more broadly-defined industry. Suppose we were looking at concentration within the shoe industry. Should the market be simply "shoes", or do we break that down further into "athletic shoes", "men's shoes", "children's shoes", etc.?

Coordinating Economic ActivityEconomic activity can be coordinated by markets or by individual firms. A firm organizes input production factors so as to produce and market goods and/or services.

Auto manufacturers are actually assemblers of cars - most the parts in a car are produced by hundreds of component suppliers. This is an example of market coordination. If General Motors decides to coordinate all activities associated with brake components, then the coordination is being done by that firm. A firm will decide to coordinate a particular type of economic activity when it can do so more efficiently than what is provided by the market.

Firms can be more efficient than markets due to:

· Economies of scope - this applies when a firm hires specialized resources that can produce a broad range of goods and services. For example, a person with a difficult to diagnose medical condition would probably be sent to a hospital, which will have a broad range of medical specialists and diagnostic equipment.

· Economies of scale - for many types of goods, per unit production costs decline as larger volumes of output are produced by an individual firm.

· Team production can often lower production costs.

· Transaction costs are often reduced when economic activity is coordinated by a firm. Suppose you want to perform a major remodeling of your house. If you decide to coordinate the work yourself, you will have significant transaction costs associated with hiring qualified personnel such as plumbers and carpenters, monitoring their work, negotiating contracts with them, finding suitable building materials, arranging for delivery of materials and coordinating

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work schedules of the various subcontractors. If you hire a building firm or general contractor to coordinate the work, they probably will have lower transaction costs because they already will have knowledge of suitable subcontractors in the area and how best to get building materials. By hiring a general contractor, you will reduce your transaction costs by only having to negotiate one contract.

Microeconomics - Modifying Output

The "Short Run"The short run is a time period so short that the firm cannot alter some production factors (typically these factors include the size and/or number of plants, the technology used, equipment and the management organization). Those factors are sometimes referred to collectively as the "plant". The firm usually can increase output in the short run by adding variable inputs. Labor is the most common variable input.

The "Long Run"In the long run, firms have sufficient time to adjust to any and all production factors. Factories can be expanded, shrunk, demolished or built. The firm can leave or enter an industry.

Suppose a car manufacture decides to build a new plant to build SUVs. This would be an example of a decision made in the long run. If that manufacturer decided to expand output by having employees work overtime, then that would be an example of a short-run decision.

Look Out!Differences between the "short run" and the "long run", and the concept of economic profit are critical to understanding economics!

Total Product: The total product is the total quantity of goods produced, in association with specified levels of input.

Marginal Product: The marginal product is the change in output that occurs when one more unit of input (such as a unit of labor) is added.

Average Product: The average product is the total product divided by the number of input units, usually a variable input such as labor.

Example:Suppose only one worker was present at an assembly plant and that worker had to do all functions of the plant - order and stock supplies, assemble the good, provide maintenance for the factory, prepare the good for shipping, etc. If a second worker is added, there may be a larger increase in productivity, as the two workers can allocate the tasks according to their abilities, and less time will be lost going to and from various locations in the plant.

A possible schedule of plant output could be as follows:

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In this example, hiring the fourth worker increases output by 110 units, which is not as large as the increase created by hiring the third worker.

The cost of all production factors is equal to the firm's total cost (TC). Total fixed costs (TFC) include all fixed costs, while total variable costs (TVC) include the cost of all variable inputs such as labor. Marginal cost is the increase in costs associated with producing additional output. At some point in time, marginal costs will begin to increase because each additional worker contributes less to total output. The average fixed cost (AFC) is the fixed cost per unit of output, while the average variable cost (AVC) specifies the variable cost per unit of output. AFC and AVC combined are equal to the average total cost (ATC). As production increases, average fixed cost (total fixed cost divided by quantity) will decrease. When marginal cost exceeds average total cost, average total costs will go up, at which point the firm must receive higher prices if higher production is to occur.

The table below assumes that the firm has fixed costs of $1,000 per day, each worker is paid $200 per day, and each unit produced has variable material costs of $1 per unit.

From the table above we can see that both average total cost and marginal cost initially decrease as production increase, but both start going up at certain levels of production.

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Microeconomics - Marginal and Average Total Cost Curves

Cost CurvesThe short-run marginal cost (MC) curve will at first decline and then will go up at some point, and will intersect the average total cost and average variable cost curves at their minimum points.

The average variable cost (AVC) curve will go down (but will not be as steep as the marginal cost), and then go up. This will not go up as fast as the marginal cost curve.

The average fixed cost (AFC) curve will decline as additional units are produced, and continue to decline.

The average total cost (ATC) curve initially will decline as fixed costs are spread over a larger number of units, but will go up as marginal costs increase due to the law of diminishing returns.

The graph below illustrates the shapes of these curves.

Figure 3.8: Cost Curves

Diminishing Returns and Diminishing Marginal Product of CapitalThe law of diminishing returns states that as one type of production input is added, with all other types of input remaining the same, at some point production will increase at a diminishing rate.

There may be levels of input where increasing inputs causes production to go up at an increasing rate. However, according to the law of diminishing returns, at some point production will go up at a decreasing rate.

The marginal product of capital is the increase in total output associated with an increase in capital, while holding the quantity of labor constant. Capital is also subject to the law of diminishing returns.

Economies of ScaleEconomies of scale mean that goods can be produced at a lower cost per good, as the quantity

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produced increases. Large-scale factory operations can permit the most efficient specialization of machinery and labor. Average fixed costs will decline as costs such as advertising can be spread across more and more units. Diseconomies of ScaleDiseconomies of scale occur when per unit costs go up as output is increased. A typical reason given is bureaucratic inefficiencies - more attention may be given to administrative rules as opposed to innovation. Worker motivation is also more difficult as the number of employees increases.

When economies of scale occur, the long-run average total cost (LRAC) curve will be declining; with diseconomies of scale, the LRAC curve will be rising.

Figure 3.9: Long Run Average Total Curve

Microeconomics - Perfectly Competitive Markets

A purely competitive (price taker) market exists when the following conditions occur:

Low entry and exit barriers - there are no restraints on firms entering or exiting the market

Homogeneity of products - buyers can purchase the good from any seller and receive the same good

Perfect knowledge about product quality, price, and cost No single buyer or seller is large enough to influence the market price

Sellers must take the existing market price; if they set a price above the market price, no one will buy their product because potential buyers simply will go to other suppliers. Setting a price below the market price does not make any sense because the firm can sell as much as it

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wants to at the market price; selling below the market price will just reduce profits.

Because sellers must take the current market price a purely competitive market is also called a "price takers" market.

The firm can sell as much as it can produce at the existing market price, so demand is not a constraint for the firm. Revenue will be simply the market price multiplied by quantity produced.

Maximizing Profit in Perfect CompetitionA price taker can sell as much as it can produce at the existing market price.

So total revenue (TR) will be simply P × Q, where P = price and Q = quantity sold.

Marginal revenue (MR), the increase in total revenue for production of one additional unit, will always be equal to the market price for a price taker.

If the market price of a good is $15, and a firm produces 10 units of a good per day, then its total revenue for the day will be $15 × 10 = $150. The marginal revenue associated with producing an eleventh unit per day would be the market price, $15; total revenue per day would increase from $150 to $165 (11 × $15).

Marginal costs will vary, depending upon the quantity produced. We would expect the firm to increase input up to the point where marginal cost is equal to the market price. In the short run, a firm will produce as long as its average variable costs do not exceed the market price. If the market price is less than the firm's total average cost, but greater than its average variable cost, then the firm will still operate in the short run. Its losses will be lowered by producing, since nothing can be done about fixed costs in the short run. Over the long run, the firm will need to cover all of it costs if it is to keep on producing.

If the market price at least covers the firm's variable costs, it may make sense to keep on operating. Any price in excess of the average variable cost will at least help to cover the fixed cost. Unless the firm decides to completely leave the business, it will come out ahead by continuing to operate.

If the market price is below the firm's average variable cost, it will not make sense for the firm to operate as it will lose even more money. If the firm believes that business conditions will improve, it will temporarily shut down. Seasonal businesses such as ski resorts or restaurants located by vacation areas will shut down temporarily at certain times. Manufacturers temporarily might shut down a factory and plan to reopen the factory when business conditions improve.

When Does a Firm Maximize Profit in Perfect Competition?Profit (π) is equal to total revenue minus total cost. We can express this mathematically by stating:π = TR - TC

In terms of calculus, we can state that profit will be maximized when the first derivative of the profit function is equal to zero:

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dπ = dTR   -dTC= 0dQ dQ dQ

We also can rearrange the terms to state that profit maximization occurs when:

Formula 3.4

dTR = dTCdQ      dQ

The term on the left represents the change in revenue from producing one more unit, which is called marginal revenue. The term on the right represents the change in total costs resulting from producing one more unit, which is marginal cost.

The firm's profit will be maximized at the level of output whereby the marginal (additional) revenue received from the last unit produced is just equal to the marginal (additional) cost incurred by producing that last unit. Maximum profit for the firm occurs at the output level where MR = MC.

For a firm operating in a competitive environment, the marginal revenue received is always equal to the market price. Therefore a firm operating under perfect competition will always produce at the level of output where the marginal cost of the last unit produced is just equal to the market price.

The following equation will hold:

Formula 3.5

MR = MC = P

Microeconomics - Effects on Equilibrium in the Short and Long Run

The Firm vs. the Industry's Short-Run Supply CurveA company will continue to produce output until marginal revenue (MR) is equal to marginal cost (MC).

In other words, the condition for maximum profit occurs where:MR = MC

Another condition for profit to be maximized, because it is possible that MR=MC at a point where MC is falling, is that the marginal cost curve must be rising. Therefore, the supply

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curve for a competitive firm will be that part of the marginal cost curve which lies above the low point of the average cost curve. The supply curve slopes upward because marginal costs increase with the greater quantity supplied in the short run. With a competitive market, the supply curve will be a summation of the individual firms' supply curves.

Long-Run Effects on Equilibrium In the short-run, increases (decreases) in demand in a competitive market will cause prices and output to increase (decrease).

In the long-run, increases (decreases) in demand in a competitive market will cause increases (decreases) in output. Initially, markets with an increase (decrease) in demand will have firms experiencing economic profits (losses). Over time, markets with firms experiencing economic profits (losses) will have additional firms enter (existing firms will exit) the market, and prices will decrease (increase) towards previous levels. If cost conditions remain the same, then prices will revert to what they were before the increase (decrease) in demand.

If the market price falls below a firm's average total cost, the firm will incur economic losses. The firm may be able to lower its average total cost by changing to a different plant size. Suppose a firm increases its plant size, and lowers its average total costs. If other firms follow, then the industry supply curve will shift to the right. This will result in lower prices and less economic profit.

If a firm does not expect market conditions to improve then it may decide to go out of business. This would be the preferred option as, by selling out, neither fixed nor variable costs would be incurred.

Impact From Changes in TechnologyThe impact of a permanent change of demand on price and output for a market will be influenced by the cost structure of suppliers in the market. The long-run market supply curve in a competitive industry will depend on the returns to scale.

For a constant-cost industry, if demand increases, then firms temporarily will make a profit as price will go above the minimum needed for the firms to stay in business. This will cause firms to expand output or new firms to enter the industry. Because costs are constant in the long run, the long-run supply curve will be horizontal. In the graph below, as demand shifts from D1 to D2, over the long run quantity will increase from Q1 to Q2. However, price will remain the same.

Figure 3.12: Long Run Supply: Constant Cost Industry

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For an increasing cost industry, if demand increases, firms will need higher prices over the long run in order to justify higher levels of production. For example, prices for raw materials used in the industry may go up with higher levels of production, which will force the long-run supply curve to slope upward.

Figure 3.10: Long Run Supply: Increasing Cost Industry

For a decreasing cost industry, if demand increases, in the long run firms can provide more output at lower prices. The need to produce larger quantities of goods and services in response to increased demand induces technological change, which lowers costs for the producer and these savings are passed on to consumers in the long run.

Figure 3.11: Long Run Supply: Decreasing Cost Industry

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Microeconomics - Characteristics of Monopolies

A monopoly is the single seller of a good for which substitutes are not readily available. There should be high barriers to entry; i.e. other firms cannot enter the market easily and provide the good.

Monopolies often are created due to legal barriers. Patent laws grant inventors the exclusive right to produce and sell a product for a period of time (typically 17 years in the United States). Licensing restrictions often limit who is allowed to provide a good or service in a particular geographic area.

In some instances, economies of scale exist so that there is a tendency toward a natural monopoly - one firm can provide the good most efficiently. One traditional example is the distribution of electrical power to a local community. Duplication of power lines within a community would increase overall costs. With natural monopolies, government policy to encourage more entrants may not make sense.

To some degree, natural monopolies occur in the computer industry, where customers want to adhere to a common standard. The common standard for personal computer operating systems is provided by Microsoft. Alternative operating systems for personal computers (such as LINUX) do not make sense for most consumers, so Microsoft has considerable monopoly power.

The Monopolist and Profit MaximizationThe monopolist has control both over the quantity produced and price charged; it also faces the entire demand curve for the good produced. Therefore, it will face a downward-sloping demand curve. It follows the general rule for profit maximization, MR = MC. As the monopolist does not know exactly how much consumers are willing to buy at particular prices, it must "search" for the optimum price.

Figure 3.12: Monopolist Profit Maximization

As shown in the graph above, a monopolist facing demand curve D0 will produce quantity Q0 and the price charged will be equal to P0.

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What happens if the monopolist later faces a demand curve such as D1? In that case, the monopolist cannot cover costs and will go out of business.

Microeconomics - Inefficiencies of Monopolies

Monopolies vs. Perfect CompetitionsA market characterized by monopoly has only a single seller, while a perfectly competitive market has many sellers. There are high barriers of entry with the monopoly, but little to no barriers to entry in the perfectly competitive market. Because the product of a monopolist cannot be substituted readily, the monopolist can set a higher price and still get sales. The seller in a perfectly competitive market cannot get a higher price because potential buyers always can get the product from other sellers.

Major inefficiencies associated with monopolies include:

·Allocative inefficiency - prices will tend to be higher, and output lower, than what would exist in a market with low barriers to entry. Prices will tend to be higher than both marginal costs and average total cost.

·Weakened market forces - when consumers of a product have many alternatives, producers must serve their customers efficiently in order to stay in business. If consumers can't purchase competitive products easily, the monopolist doesn't need to worry a lot about losing customers when poor service or a poor quality good is provided.

·Rent or favor seeking - firms and/or individuals will put a great deal of effort into obtaining or maintaining high entry barriers; by doing so, they hope to achieve monopoly-type profits. Such efforts enrich some people, at the expense of many others.

Price DiscriminationPrice searchers effectively price discriminate among their customers when they are able to:

a) identify sub-groups which have different elasticities of demand, andb) ensure that the customers cannot resell the good.

A common example is airline travel. Travelers who plan in advance will have a higher elasticity of demand than travelers who must travel within a short period of time.

With price discrimination, some consumers pay higher prices than they would if there was a single price. However, many in the group paying lower prices will now be getting something they otherwise would not have purchased. Universities are increasing their use of price discrimination. Tuition rates for students without financial aid are increasing greatly while the average price charged is not going up as much because more financial aid is being offered. The colleges reap high revenues from wealthy families who can afford to pay high tuition while more students from lower-income families can now attend college.

In general, higher output will occur with price discrimination. Furthermore, there may be some businesses that could not exist without price discrimination. For example, a dentist in a small town may not have a viable business without performing price discrimination.

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As price discrimination increases output and gains from trade, it reduces allocative inefficiency. Firms that successfully price discriminate will benefit by getting higher revenues.

Why Do Monopolies Exist?If a natural monopoly is to exist, the government can regulate the price and output. In the graph below, the monopolist would prefer to charge price P1 and Q1 to maximize profits. A regulatory agency will often set the price at P2. At this price, the monopolist receives enough to cover costs and, in effect, it receives a competitive rate or return of its capital. The benefits to society from the increased production outweigh the increased costs to the monopolist.

Figure 3.13: Results of Regulating Price and Output

Microeconomics - Monopolistic Competition

A firm engaged in monopolistic competition which is considering reducing prices in order to increase total revenue has two conflicting factors to consider. Reducing prices will increase the quantity of a good sold, but the reduction in price will also apply to quantities of the good that would have been sold at a higher price.

The price searcher can maximize profit by adjusting output and the price until marginal revenue is equal to marginal cost. Notice that the marginal revenue curve lies below the firm's demand curve.

Figure 3.15: Marginal Revenue Curve In Monopolistic Competition

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The phrase "contestable markets" describes markets where there are few sellers, but they behave in a competitive manner because of the threat of new entrants. For instance, an airline may serve a particular route exclusively, but does not charge excessive prices because those prices would entice additional airlines to offer that route.

Government regulation is often used to keep new firms out of markets. Economists generally favor deregulation as this helps to keep prices low.

Prices over the long run in a competitive market will move to the lowest point of the firm's average total cost curve. We then have allocative efficiency because desired goods are produced at the lowest possible cost.

Because price searchers face downward-sloping demand curves, the price they charge will exceed the firm's marginal cost. The price charged and the quantity produced will not be where the firm minimizes average total costs. Figure 3.16 illustrates these points.

Figure 3.16: Monopolistic Competition: Low Barriers to Entry

The monopolistic competition market, in comparison to a purely competitive market, will have a higher price and lower output. Some argue that this is a good trade-off, as consumers benefit from having a variety of goods. Advertising would be not be used by price-takers, but is used by price-searchers; as the cost of advertising is ultimately borne by consumers, it is an argument against the price-searcher market. If barriers to entry are low, firms still have an incentive to produce efficiently, use resources only if they add value and innovate by altering their products or offering new products. Entrepreneurs may have more incentives with price searcher markets, while if markets are contestable, prices will not be excessively higher than

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those in competitive markets.

Product Development and Marketing in Monopolistic CompetitionFirms engaged in monopolistic competition invest in product development and marketing so as to differentiate themselves from other firms in the industry. By doing so, they hope to gain more monopolistic pricing power. Since advertising increases costs, it will shift supply curves up and to the right. Ultimately, over the long run, consumers pay for the advertising in the form of higher prices.

In comparison to the pure competitive market, prices will be higher and quantities produced will be lower when there is monopolistic competition. However, there will be a greater variety of goods. This may be a worthwhile tradeoff.

Microeconomics - Oligopolies

What is an Oligopoly?Oligopoly refers to a market with "few sellers". Oligopolies interact among themselves. When an oligopolist changes a price, it must take into account how other firms in the industry will respond. Within an oligopoly, the products can be similar or differentiated. Oligopoly markets have high barriers to entry.

The Prisoner's DilemmaThe "prisoners' dilemma" was first described in the field of "game theory", which is a branch of applied mathematics and economics dealing with choices made under conflict and uncertainty. Suppose that the police believe Dave and Henry have committed a felony, but the evidence is weak. The police have placed Dave and Henry in jail, in separate cells. The police need the confession of at least one of the prisoners in order to get a felony conviction. If neither prisoner confesses, then the police can only convict them on a minor charge with a three-month prison term. Each prisoner is offered the following deal: if one testifies against the other while the other remains the silent, the one who testifies will not be convicted of anything, while the one who remains silent will go to jail for 20 years. If both confess, then each will receive a five-year jail term.

To sum up the situation:

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The optimum result for the two together is to stay silent, in which Dave and Henry will each get only three months prison time. However, each prisoner does not have knowledge of what the other prisoner will do. The most rational response from the individual is to confess. If the other prisoner stays silent, then that person gets off free; if the other prisoner confesses, then the prison term will be less (five years vs. 20 years).

The prisoners' dilemma illustrates a situation in which individuals arrive at a non-optimal solution, due to a lack of cooperation and trust. A similar situation occurs with oligopolies. If firms within an oligopolistic industry have cooperation and trust with each other, then they can theoretically maximize industry profits by setting a monopolistic price. Firms would then have to figure out how to fairly divide up the profits.

If oligopolies collude successfully, they will set price and output such that MR = MC for the industry overall. In figure 3.17 on the following page, this is depicted as Pa and Qa. Without collusion, firms will lower prices to attract more customers. Gradually, the price and output will move to Pb and Qb, which is identical to what would be achieved with a competitive market.

Figure 3.16: Oligopolist Profit Maximization

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Oligopolies have strong incentives to collude because while acting together, they can restrict output and set prices so that economic profits are earned. The individual oligopolist has an incentive to cheat because the firm's demand curve is more elastic than the overall market demand curve. By secretly lowering prices, the firm can sell to customers who would not buy at the higher price, as well as to customers who normally buy from the other firms.

Oligopolistic agreements tend to be unstable due to these conflicting tendencies.

Obstacles to collusion within oligopolies include:

Low Entry Barriers - Particularly as time goes on, more firms will be attracted to the potential economic profits, which will not be sustainable. For example, the OPEC's raising of oil prices during the 1970s and early 1980s enticed more non-OPEC producers to produce more. The market share of OPEC producers was drastically reduced and they had to reduce prices in order to gain market share. In the long run, cartels are not usually successful at raising prices.

Antitrust Laws - these laws prohibit collusion. Although firms may make secret agreements, those agreements will not be enforceable in a court of law.

Unstable Demand Conditions - These conditions will make collusion more difficult, as firms are more likely to have disagreements as to what is the best direction for the industry. Some may expect large increases in demand, while others may disagree and prefer that industry capacity remains the same.

Increasing Number of Firms - An increasing number of firms in an oligopolistic industry will make agreements harder to discuss, negotiate and enforce. Differences of opinion are more likely. As the number of firms in the industry increases, the industry will behave more like a competitive market.

Difficulties with Detecting and Stopping Price Cuts - These difficulties will undermine effective collusion. Sometimes oligopolistic firms will cheat by enacting quality improvements, easier credit terms and free shipping. If quality changes can be used to compete, collusive price agreements will not be effective.

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Microeconomics - Conclusion Within this Section we have focused on the basics of microeconomics, the properties of demand and supply, price takers and searchers, and demand and supply for resources and capital. For a quick review, we've summarized the characteristics of the various market types below.

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