Honest Signaling and the Maxim of Quality - University of

26 Pages·2013·0.37 MB·English

by  Christopher Ahern

Honesty Mechanisms Reputation Gossip Language
Honest Signaling and the Maxim of Quality
Christopher Ahern
UniversityofPennsylvania
April 13, 2013
Ahern (UPENN) HonestSignalingandtheMaximofQuality April13,2013 1/26
Honesty Mechanisms Reputation Gossip Language
What keeps language meaningful?
Why don’t we say things we know to be false?
Why don’t we say things for which we lack evidence?
Why should we care?
Can we ground our assumptions?
Can we integrate more aspects of meaning?
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Honesty Mechanisms Reputation Gossip Language
Outline
1 Honesty
2 Mechanisms
3 Reputation
4 Gossip
5 Language
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Honesty Mechanisms Reputation Gossip Language
Honesty as Cooperation
Cooperation
When a self-interested agent incurs a cost (c) to confer a benefit (b) on
another agent.
Prisoner’s Dilemma
Cooperate Defect
Cooperate b−c, b−c −c, b
Defect b, −c 0,0
Where b > c > 0, defection is the dominant strategy, and mutual
defection the only equilibrium.
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Honesty Mechanisms Reputation Gossip Language
Honesty in Signaling
Prisoner’s Dilemma
Cooperate Defect
Cooperate b−c, b−c −c, b
Defect b, −c 0,0
“I am going to cooperate!”
Is the signal credible?
If it is true you should defect.
If it isn’t true you should still defect.
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Honesty Mechanisms Reputation Gossip Language
Cooperation vs. Coordination
A B Cooperate Defect
A b, b 0, 0 Cooperate b−c, b−c −c, b
B 0, 0 b, b Defect b, −c 0,0
Signals are credible in games of coordination, but not in games of
cooperation.
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Honesty Mechanisms Reputation Gossip Language
Honest Signaling and Deception
Deception Undermines Signaling
Signals cease to reliably correlate with any aspect of the sender.
Gullible receivers do worse than skeptics.
Skeptical receivers do not attend to signals.
Senders shouldn’t bother signaling if receivers don’t attend to
signals.
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Honesty Mechanisms Reputation Gossip Language
General Classes of Mechanisms (Scot-Phillips 2010)
Indices
Signal form is tied to signal meaning.
Handicaps
Signal cost is tied to signal form. Cost is incurred by reliable/honest
signalers.
Deterrents
Costs are incurred (at least partially) by dishonest senders.
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Honesty Mechanisms Reputation Gossip Language
General Classes of Mechanisms (Scot-Phillips 2010)
Indices
Language is arbitrary.
Handicaps
Lying and telling the truth require the same amount of effort.
Deterrents
Many possibilities.
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Honesty Mechanisms Reputation Gossip Language
Reputation
Three basic components (Trivers, 1971)
Ability to recognize individual agents
Keep track of past interactions
Condition future behavior on past interactions
Iterated Prisoner’s Dilemma with Choice and Refusal
Agents have propensity to interact with each other.
Results of interactions change this over time.
Agents can choose who to interact with (or not) over time.
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