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Introduction Intention Commitment Apology Conclusions
Emergence of Collective Behavior and AI:Intention Recognition, Commitment and Apology
The Anh HanArtificial Intelligence Lab, Vrije Universiteit Brussel
Guest Lecture, Current Trends in Artificial Intelligence,VUB/ULB
April 25, 2014
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Introduction Intention Commitment Apology Conclusions
Outline
1. Introduction• Explaining the evolution of cooperation (state-of-the-art and
methods)• Evolution of cooperative behavior in AI research
2. Evolution of Cooperation• Intention recognition• Commitment (pairwise and group interactions)• Apology
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Introduction Intention Commitment Apology Conclusions
What is Cooperation?
• pay a cost for someone else to receive a benefit.
• Cooperation is widespread: insects, hunter-gatherer societies,team work, international relationships, etc.
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Introduction Intention Commitment Apology Conclusions
Paradox of cooperation
If natural selection is based on competition, how can it lead to cooperation?
• Natural selection: only the fittestsurvive
• Everyone wants to increase theirfitness.
• No one wants to pay the cost,happily accepting benefits.
• Dilemma: everyone would bebetter off cooperating with eachother (benefit > cost).
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Introduction Intention Commitment Apology Conclusions
Interdisciplinary research
• Understanding the evolution of cooperation remains afundamental challenge, for scientists from fields likeevolutionary biology, physics, economics, mathematics,computer science & AI1, etc.
• Many fields ... same math!!
• Mathematical Framework: Evolutionary Game Theory &Agent-based Simulations
• Metaphors: Prisoner’s dilemma, Public Goods Game,Ultimatum game, etc.
1IJCAI, AAMAS, CEC, GECCO, ALIFE, COGNITION5 / 69
Introduction Intention Commitment Apology Conclusions
Interdisciplinary research
• Understanding the evolution of cooperation remains afundamental challenge, for scientists from fields likeevolutionary biology, physics, economics, mathematics,computer science & AI1, etc.
• Many fields ... same math!!
• Mathematical Framework: Evolutionary Game Theory &Agent-based Simulations
• Metaphors: Prisoner’s dilemma, Public Goods Game,Ultimatum game, etc.
1IJCAI, AAMAS, CEC, GECCO, ALIFE, COGNITION6 / 69
Introduction Intention Commitment Apology Conclusions
Evolutionary Game Theory
payoff → fitness → social success
Individuals with higher fitness will reproduce more
genetic evolution
cultural/social evolution
OR their behavior will be imitated more often
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Introduction Intention Commitment Apology Conclusions
Imitation and Reproduction Processes
• Players with lowest fitness imitate or are replaced by the oneswith highest fitness in the population.
• Imitation/replacement probability: player B imitates playerA’s strategy with probability
PB→A =[1 + e−β(fA−fB)
]−1
• fA and fB are the payoffs (fitnesses) of A and B;• β is called imitation strength, which controls how strong the
payoffs play a role in the imitation decision;
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Introduction Intention Commitment Apology Conclusions
Imitation and Reproduction Processes
• Players with lowest fitness imitate or are replaced by the oneswith highest fitness in the population.
• Imitation/replacement probability: player B imitates playerA’s strategy with probability
PB→A =[1 + e−β(fA−fB)
]−1
• fA and fB are the payoffs (fitnesses) of A and B;• β is called imitation strength, which controls how strong the
payoffs play a role in the imitation decision;
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Introduction Intention Commitment Apology Conclusions
Evolutionary Game Theory
payoff → fitness → social success
Natural selection leads to the destruction ofcooperation (tragedy of commons).
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Introduction Intention Commitment Apology Conclusions
Mechanisms of cooperation a
• kin selection: the more individuals arerelated, the more cooperation is feasible
• direct reciprocity: repeated interactions,memory
• indirect reciprocity: reputation basedstrategies
• group selection, structured population,punishment, etc.
aM. Nowak. Five rules for the evolution of cooperation. Science, 2006
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Introduction Intention Commitment Apology Conclusions
Mechanisms of cooperation a
• kin selection: the more individuals arerelated, the more cooperation is feasible
• direct reciprocity: repeated interactions,memory
• indirect reciprocity: reputation basedstrategies
• group selection, structured population,punishment, etc.
aM. Nowak. Five rules for the evolution of cooperation. Science, 2006
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Introduction Intention Commitment Apology Conclusions
Where is cognition?
• Black-or-white, simple strategies.
• Humans (and other species) arecognitively skillful: mind reading,intention, learning, negotiation,commitment, anticipation, etc.
• What are the roles of cognition inthe evolution of cooperation?
• Little attention here!!!
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Introduction Intention Commitment Apology Conclusions
Where is cognition?
• Black-or-white, simple strategies.
• Humans (and other species) arecognitively skillful: mind reading,intention, learning, negotiation,commitment, anticipation, etc.
• What are the roles of cognition inthe evolution of cooperation?
• Little attention here!!!
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Introduction Intention Commitment Apology Conclusions
Where is cognition?
• Black-or-white, simple strategies.
• Humans (and other species) arecognitively skillful: mind reading,intention, learning, negotiation,commitment, anticipation, etc.
• What are the roles of cognition inthe evolution of cooperation?
• Little attention here!!!
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Introduction Intention Commitment Apology Conclusions
Where is cognition?
• Black-or-white, simple strategies.
• Humans (and other species) arecognitively skillful: mind reading,intention, learning, negotiation,commitment, anticipation, etc.
• What are the roles of cognition inthe evolution of cooperation?
• Little attention here!!!
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Introduction Intention Commitment Apology Conclusions
Evolution of Cooperative Behavior as AI Research
Evolution of Cooperation
Cognitive ModelingMind-reading, Intention,
Belief, Reasoning, Learning, Prediction
Multi-agent SystemsCollaborative, Self-
organized, Decentralized systems; Markets design
Robotics Swam intelligence, Self-organization,
Coordination
Network ScienceSocial networks,
Cooperation in network, Spatial systems
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Introduction Intention Commitment Apology Conclusions
Intention reading promotes cooperation
• AI cognitive modeling combinedwith Evolutionary Game Theorymodeling.
• Recognizing intention helpschoosing cooperative partners andavoiding free-riders and exploiters.
• Recognizing intentions enablesstrategies with shorter memories.
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Introduction Intention Commitment Apology Conclusions
Intention recognition research in AI
Set of Intentions
Plan Library Plan CorpusAction Theory
A1 A2 A3 ....... Model-Bayesian KB-Markov KB
....
Sequence of Observed Actions
Recognized Intentions
With Rankings (Probabilistic) Without Rankings (Non-probabilistic)
Observed Agent
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Introduction Intention Commitment Apology Conclusions
Intention recognition promotes emergence of cooperationin repeated interactions
Intention recognizers can effectively detect (using BayesianNetwork inference)
1. ‘good’ and ‘bad’ 2
2. ‘unconditionally good’ , ‘conditionally good’, and ‘bad’ 3 4
Intention recognizers quickly learn to cooperate with eachother.
2Han, Pereira, Santos. Intention recognition promotes emergence of cooperation. Adaptive Behavior, 2011
3Han, Pereira, Santos. Corpus-based intention recognition in cooperation dilemmas. Artificial Life, 2012
4Han, Pereira, Santos. The role of intention recognition in evolution of cooperative behavior. IJCAI, 2011
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Introduction Intention Commitment Apology Conclusions
Intention recognition promotes emergence of cooperationin repeated interactions
Intention recognizers can effectively detect (using BayesianNetwork inference)
1. ‘good’ and ‘bad’ 2
2. ‘unconditionally good’ , ‘conditionally good’, and ‘bad’ 3 4
Intention recognizers quickly learn to cooperate with eachother.
2Han, Pereira, Santos. Intention recognition promotes emergence of cooperation. Adaptive Behavior, 2011
3Han, Pereira, Santos. Corpus-based intention recognition in cooperation dilemmas. Artificial Life, 2012
4Han, Pereira, Santos. The role of intention recognition in evolution of cooperative behavior. IJCAI, 2011
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Introduction Intention Commitment Apology Conclusions
Intention recognition promotes emergence of cooperationin repeated interactions
Intention recognizers can effectively detect (using BayesianNetwork inference)
1. ‘good’ and ‘bad’ 2
2. ‘unconditionally good’ , ‘conditionally good’, and ‘bad’ 3 4
Intention recognizers quickly learn to cooperate with eachother.
2Han, Pereira, Santos. Intention recognition promotes emergence of cooperation. Adaptive Behavior, 2011
3Han, Pereira, Santos. Corpus-based intention recognition in cooperation dilemmas. Artificial Life, 2012
4Han, Pereira, Santos. The role of intention recognition in evolution of cooperative behavior. IJCAI, 2011
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Introduction Intention Commitment Apology Conclusions
Why arrange commitments?
• Sometimes difficult to predict others’ behavior orrecognize their intentions with sufficient confidence.
• Commitment proposal can help clarify intentions of others.• contracts, marriage, apartment rental, etc.
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Introduction Intention Commitment Apology Conclusions
Why arrange commitments?
• Sometimes difficult to predict others’ behavior orrecognize their intentions with sufficient confidence.
• Commitment proposal can help clarify intentions of others.• contracts, marriage, apartment rental, etc.
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Introduction Intention Commitment Apology Conclusions
Prisoner’s Dilemma (PD)
✓ C D
C R, R S, TD T, S P, P
◆• C: cooperate; D: Defect
• T > R > P > S
• T = temptation to defect
• R = reward
• P = punishment
• S = sucker’s payoff
• D is always the best individual’schoice but everyone plays C is thebest outcome for the population.
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Introduction Intention Commitment Apology Conclusions
Prisoner’s Dilemma (PD)
✓ C D
C R, R S, TD T, S P, P
◆• C: cooperate; D: Defect
• T > R > P > S
• T = temptation to defect
• R = reward
• P = punishment
• S = sucker’s payoff
• D is always the best individual’schoice but everyone plays C is thebest outcome for the population.
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Introduction Intention Commitment Apology Conclusions
Commitment strategy (COMP)
When meeting a co-player (to play PD)
• proposes its co-player to commit tocooperate.
• if accepted,• Pay the cost ε of setting up the
commitment.• Cooperate in the game and receive
payoff.• If opponent defects, get
compensation δ.
• if not accepted• Don’t play the game, hence 0 reward.
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Introduction Intention Commitment Apology Conclusions
What are the strategies of the co-players
• Cooperator (C): always acceptscommitment.
• Defector (D): never acceptscommitment.
• Fake committer (FAKE): acceptscommitment, yet defects in game.
• Commitment free-rider (FREE): accepts commitment andcooperates, yet defects when receiving no commitmentproposal.
There are other potential strategies yet they are all domi-nated by one of these.
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Introduction Intention Commitment Apology Conclusions
What are the strategies of the co-players
• Cooperator (C): always acceptscommitment.
• Defector (D): never acceptscommitment.
• Fake committer (FAKE): acceptscommitment, yet defects in game.
• Commitment free-rider (FREE): accepts commitment andcooperates, yet defects when receiving no commitmentproposal.
There are other potential strategies yet they are all domi-nated by one of these.
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Introduction Intention Commitment Apology Conclusions
Commitment strategy
Payoff matrix for the five strategies
COMP C D FAKE FREE
COMP R − ε/2 R − ε 0 S + δ − ε R − εC R R S S SD 0 T P P PFAKE T − δ T P P PFREE R T P P P
.
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Introduction Intention Commitment Apology Conclusions
Viability of COMP
• Risk-dominance: indicates whether a strategy isviable with respect to the other strategies.
• Consider any two strategies A and B, A is said to berisk dominant against B when
πA,A + πA,B > πB,A + πB,B
where πX ,Y is the (average) payoff of strategist Xwhen interacting with strategist Y.
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Introduction Intention Commitment Apology Conclusions
Viability of COMP
For which cost ε and compensation δ COMP is viable againstD, FAKE and FREE
1. ε < min {2(R − P), 2(R − P)/3}2. δ > (T − R + P − S)/2 + 3ε/4.
Simplifying: T = b,R = b − c ,P = 0 and S = −c
1. ε < 2(b − c)/3: The cost should be smaller than the benefitof cooperation.
2. δ > c + 3ε/4: The compensation should be sufficiently largewith respect to the cost of cooperation and of commitment.
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Introduction Intention Commitment Apology Conclusions
Viability of COMP
For which cost ε and compensation δ COMP is viable againstD, FAKE and FREE
1. ε < min {2(R − P), 2(R − P)/3}2. δ > (T − R + P − S)/2 + 3ε/4.
Simplifying: T = b,R = b − c ,P = 0 and S = −c
1. ε < 2(b − c)/3: The cost should be smaller than the benefitof cooperation.
2. δ > c + 3ε/4: The compensation should be sufficiently largewith respect to the cost of cooperation and of commitment.
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Introduction Intention Commitment Apology Conclusions
Viability of COMP
COMP69%
C5%
D13%
FAKE3%
2.0ρN
9.5ρN
9.5ρN
24.1ρN
FREE10%
9.5ρN
5.6ρN
2.4ρN
Figure: Stationary distributions for a viable solution:δ = 4, ε = 0.25, b = 2, c = 1.
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Introduction Intention Commitment Apology Conclusions
Viability of COMP
10
δ
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COMP C FAKED FREE
COMS CS FAKS FRES
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0.6
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6
0.0 0.2 0.4 0.0
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Introduction Intention Commitment Apology Conclusions
Sharing the cost?
dC 0.78
0.73
0.56
0.63
0.42
0.28
0.14
0.0 0.5 1.0 1.5 0.0 0.2 0.4 0.6 0.8
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Freq
uenc
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δ
1. ε < 2(b − c)/3→ ε < 2(b − c): higher costs allowed
2. δ > c + 3ε/4→ δ > c + ε/4: smaller compensations possible
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Introduction Intention Commitment Apology Conclusions
Conclusions: commitments 5 6
• When the cost of commitment is justified with respect to thebenefit of the cooperation and the compensation is sufficientlyhigh, cooperation can thrive.
• Sharing costs leads to even better friends; cooperation for awider range of parameter values
5Han, Pereira, Santos. Emergence of commitment and cooperation. AAMAS, 2012.
6Han, Pereira, Santos, and Lenaerts. Good agreements make good friends. Nature Scientific Reports, 2013.
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Introduction Intention Commitment Apology Conclusions
Why apologize?
• Sincere apology can resolve conflicts and misunderstandings.
• Involving external parties (e.g. courts) may cost all sides of aconflict significantly more.
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Introduction Intention Commitment Apology Conclusions
Why to apologize not?
• Sincere, acceptable apology may be too costly (e.g. losingface, reputation).
• No sufficient incentive to apologize (e.g. commitment-freeinteractions).
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Introduction Intention Commitment Apology Conclusions
Questions to be asked about apology
• We build computational models to study whether (and how)explicit apology can lead to the emergence of cooperation:
• Would apology need to be sincere (to function properly)?
• May apology lead to high levels of cooperation by itself?
• Abundance and sincerity of apology in committedrelationships vs. in commitment-free relationships?
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Introduction Intention Commitment Apology Conclusions
Apology in repeated games under noise
• Typically (sincere) apology occurs in repeated interactionsettings, to ensure future long-term cooperation.
• Apology is usually modeled implicitly as one or morecooperative acts after a wrongful defection due to noise.
• ’I hit you once, you are allowed to hit me back’.
TFT (tit-‐for-‐tat): C C *D C D ...TFT (tit-‐for-‐tat): C C C D C ...
Noise
41 / 69
Introduction Intention Commitment Apology Conclusions
Apology in repeated games under noise
• Typically (sincere) apology occurs in repeated interactionsettings, to ensure future long-term cooperation.
• Apology is usually modeled implicitly as one or morecooperative acts after a wrongful defection due to noise.
• ’I hit you once, you are allowed to hit me back’.
TFT (tit-‐for-‐tat): C C *D C D ...TFT (tit-‐for-‐tat): C C C D C ...
Noise
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Introduction Intention Commitment Apology Conclusions
Explicit Apology
• It is more natural to explicitly apologize to resolve conflictbefore the next interaction occurs.
Apologizer: C C *D C C ...Apologizer: C C C C C ...
I am so sorry
Noise
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Introduction Intention Commitment Apology Conclusions
Models: Apology with and without Commitments
• COMA: propose commitments and apologize when makingmistake.
• If the co-player commits, interacts; otherwise, no interaction.• When the co-player commits, but defects and does not
apologize, ends the relationship.
• AP: pure apologizers, do not arrange commitments.
• Defecting strategies (always defect when playing)• AllD (pure defectors): don’t commit when being asked to.• FAKA (fake apologizers): commit, but don’t apologize.• FAKC (fake committers): commit, and apologize.
44 / 69
Introduction Intention Commitment Apology Conclusions
Models: Apology with and without Commitments
• COMA: propose commitments and apologize when makingmistake.
• If the co-player commits, interacts; otherwise, no interaction.• When the co-player commits, but defects and does not
apologize, ends the relationship.
• AP: pure apologizers, do not arrange commitments.
• Defecting strategies (always defect when playing)• AllD (pure defectors): don’t commit when being asked to.• FAKA (fake apologizers): commit, but don’t apologize.• FAKC (fake committers): commit, and apologize.
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Introduction Intention Commitment Apology Conclusions
Models: Apology with and without Commitments
• COMA: propose commitments and apologize when makingmistake.
• If the co-player commits, interacts; otherwise, no interaction.• When the co-player commits, but defects and does not
apologize, ends the relationship.
• AP: pure apologizers, do not arrange commitments.
• Defecting strategies (always defect when playing)• AllD (pure defectors): don’t commit when being asked to.• FAKA (fake apologizers): commit, but don’t apologize.• FAKC (fake committers): commit, and apologize.
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Introduction Intention Commitment Apology Conclusions
Key parameters
• Apology cost (γ): Apologizer compensates co-player after adefection (the higher the more sincere).
• Arrangement cost (ε): Commitment proposer has to pay anarrangement cost.
• Compensation cost (δ): Committed defaulting player has tocompensate the non-defaulting one.
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Introduction Intention Commitment Apology Conclusions
Key parameters
• Apology cost (γ): Apologizer compensates co-player after adefection (the higher the more sincere).
• Arrangement cost (ε): Commitment proposer has to pay anarrangement cost.
• Compensation cost (δ): Committed defaulting player has tocompensate the non-defaulting one.
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Introduction Intention Commitment Apology Conclusions
Apology is more frequent in committed relationships
0.83
0.81
0.750.62
0.3
0.54
0.46
0.33
0.160.040.1
Apology With Commitment (COMA)
b/c
apology cost/sincerity level (ɣ)
1
2
3
4
5
6
7
1
2
3
4
5
6
7
bene
fit-to
-cos
t rat
io (b
/c)
Apology Without Commitment (AP)
1
0
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Introduction Intention Commitment Apology Conclusions
Apology needs to be sincere to function properly
0.83
0.81
0.750.62
0.3
0.54
0.46
0.33
0.160.040.1
Apology With Commitment (COMA)
b/c
apology cost/sincerity level (ɣ)
1
2
3
4
5
6
7
1
2
3
4
5
6
7
bene
fit-to
-cos
t rat
io (b
/c)
Apology Without Commitment (AP)
1
0
50 / 69
Introduction Intention Commitment Apology Conclusions
Commitments bring about sincerity
COMA vs. AP
Ú
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51 / 69
Introduction Intention Commitment Apology Conclusions
Apology supported by commitment (COMA) prevails
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noise level (𝞪)
COMA AllC AllD FAKA
TFTFAKC
WSLSGTFT
COMA wins Without COMA Defectors win
52 / 69
Introduction Intention Commitment Apology Conclusions
Viability of COMA
• They can avoid being exploited by AllD, winning when
ε <2(1− 2α)
1− ω(b − c)
• They can get rid of fake committers FAKC, winning when
γ >3(1− ω)
4(1− 2α)ε+ c
• They can get rid of fake apologizers FAKA, winning when
δ > a2γ + a1ε+ a0
• Parameters: c - cost of cooperation; b - benefit cooperation;α - noise level; ω: probability that next round occurs.
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Introduction Intention Commitment Apology Conclusions
Conclusions: apology and commitment 7
• Apology needs to be sincere to function properly, whether in acommitted or commitment-free relationship.
• Apology supported by commitment promotes high levels ofcooperation.
• Commitments bring about sincerity in apology.
7Han, Pereira, Santos, Lenaerts. Why is it so hard to apologize? IJCAI’2013.
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Introduction Intention Commitment Apology Conclusions
Conclusions: apology and commitment 7
• Apology needs to be sincere to function properly, whether in acommitted or commitment-free relationship.
• Apology supported by commitment promotes high levels ofcooperation.
• Commitments bring about sincerity in apology.
7Han, Pereira, Santos, Lenaerts. Why is it so hard to apologize? IJCAI’2013.
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Introduction Intention Commitment Apology Conclusions
Conclusions: apology and commitment 7
• Apology needs to be sincere to function properly, whether in acommitted or commitment-free relationship.
• Apology supported by commitment promotes high levels ofcooperation.
• Commitments bring about sincerity in apology.
7Han, Pereira, Santos, Lenaerts. Why is it so hard to apologize? IJCAI’2013.
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Introduction Intention Commitment Apology Conclusions
Conclusions
• Intention recognition promotes cooperation in repeatedgames.
• Enable to choose cooperative partners and avoid free-riders.• Dealing well with noise, hence high level of cooperation.
• Arranging commitments provides incentive to cooperateeven in one-shot interactions
• Compensation must be sufficiently high compared to costs.• Shared cost is even better.
• Apology promotes cooperation if sincere• More efficient with commitment.• Commitment brings about sincerity.
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Introduction Intention Commitment Apology Conclusions
Conclusions
• Intention recognition promotes cooperation in repeatedgames.
• Enable to choose cooperative partners and avoid free-riders.• Dealing well with noise, hence high level of cooperation.
• Arranging commitments provides incentive to cooperateeven in one-shot interactions
• Compensation must be sufficiently high compared to costs.• Shared cost is even better.
• Apology promotes cooperation if sincere• More efficient with commitment.• Commitment brings about sincerity.
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Introduction Intention Commitment Apology Conclusions
Conclusions
• Intention recognition promotes cooperation in repeatedgames.
• Enable to choose cooperative partners and avoid free-riders.• Dealing well with noise, hence high level of cooperation.
• Arranging commitments provides incentive to cooperateeven in one-shot interactions
• Compensation must be sufficiently high compared to costs.• Shared cost is even better.
• Apology promotes cooperation if sincere• More efficient with commitment.• Commitment brings about sincerity.
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Introduction Intention Commitment Apology Conclusions
Potential directions
• Other cognitive abilities?
• Any wisdom?
• AI modeling & build EGT models → Agent-based simulations.
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Introduction Intention Commitment Apology Conclusions
Potential directions
• Other cognitive abilities?
• Any wisdom?
• AI modeling & build EGT models → Agent-based simulations.
61 / 69
Introduction Intention Commitment Apology Conclusions
Potential directions
• Other cognitive abilities?
• Any wisdom?
• AI modeling & build EGT models → Agent-based simulations.
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Introduction Intention Commitment Apology Conclusions
Potential directions – Master Theses??
AI Cognitive Modeling Techniques Agent-based simulation & EGT
Theory-of-mind Preference & Belief Formation
Anticipation & prediction Reasoning (abduction, reduction, ...)
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Introduction Intention Commitment Apology Conclusions
Cooperators
AI lab, Computer science department, Vrije Universiteit Brussel, Belgium
Tom Lenaerts Luis Martinez
Jean-Sebastian
David Catteeuw
Machine Learning Group, Université Libre de Bruxelles
Ioannis Zisis
Luis Moniz Pereira, AI Centrer, Universidade Novade Lisboa, Portugal
Francisco C. Santos INESC-ID and Instituto Superior Técnico, TU Lisbon, Portugal
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Introduction Intention Commitment Apology Conclusions
Thank you!
QUESTIONS?
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Introduction Intention Commitment Apology Conclusions
Replicator Equation
• Populations are infinite;
• There is a fraction xC of Cs;
• hence, xD = 1− xC is the faction of Ds.
• Populations are well-mixed: everybody is equally likely tointeract with everybody else.
• Evolution dynamics is determined by replicator dynamics:strategies’ evolution follow the gradient of natural selectiondetermined by relative fitness.
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Introduction Intention Commitment Apology Conclusions
Replicator Equations
Replicator equations for two strategies (C and D){
˙xC = xC
(fC (−→x )− φ(−→x )
)
˙xD = xD
(fD(−→x )− φ(−→x )
)
Those strategies whose fitness f (reproductive success) exceeds theaverage fitness φ of the population will increase in frequency; thosethat don’t will decline.
Replicator equations for n strategies
xi = xi
(fC (−→x )− φ(−→x )
), φ(−→x ) =
n∑
j=1
xj fj(−→x )
where xi is the fraction of xi in the population; −→x = (x1, ..., xn);fi (−→x ) is the fitness of strategy i ; φ(−→x ) is the average population
fitness.
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Introduction Intention Commitment Apology Conclusions
Future directions – Master Theses??
1. How mind-reading can help resolve the dilemmas ofcooperation and coordination between self-interested agents?
2. What kind of preferences is more relevant in a given context,e.g. preferring to interact with a greedy/unfair family memberor a generous/fair stranger?
3. How do adaptive aspirations in choosing partners influence thedynamics of cooperation and competition?
4. How to infer relevant patterns of behavior from largebehavioral experimental data where human participantsinteract with each other on a network?
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Introduction Intention Commitment Apology Conclusions
Han, T. A., Pereira, L. M., and Santos, F. C. 2011a.Intention recognition promotes the emergence of cooperation.Adaptive Behavior, 19(3):264–279.
Han, T. A., Pereira, L. M., and Santos, F. C. 2011b.The role of intention recognition in the evolution ofcooperative behavior.In Walsh, T., editor, Proceedings of the 22nd internationaljoint conference on Artificial intelligence (IJCAI’2011), pages1684–1689. AAAI.
Han, T. A., Pereira, L. M., and Santos, F. C. 2012.Corpus-based intention recognition in cooperation dilemmas.Artificial Life journal, 18(4):365–383.
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