Tit for tattling: Cooperation, communication, and how each could stabilize the other
warning: very drafty, many things get repeated and the order is kinda messed up
1 Introduction
Notion of indirect reciprocity
for reasons altruism produces a second-order benefit compensating for its first-order cost, making it potentially evolutionarily viable.
communication is required to disseminate reputation.
Under what conditions does the interaction between signaling and cooperation stabilize both high levels of (altruistic) cooperation and truthful, informative, and forthcoming (i.e. effective) communication?
Model: agents evolve over act in a prisoner’s dilemma and communicate about the actions of others
Under the conditions that allow for a stable cooperative-communicative state, agents
- act and signal according to an aligned norm
- occasionally deviate from their strategy
- exert normative pressure on each other’s signals → favors altruism and truthfulness
2 Background
called norm when the strategy encodes a set of rules that is followed by the large majority of a social group. image-scoring, which says that ‘cooperate with cooperators, defect with defectors’ standing (defined recursively: some- one is in good standing if they cooperated, or if they defected against someone in bad standing), Stern judging, similar to standing, additionally puts those who cooperate with those in bad standing into bad standing
all create an incentive to heed an opponent’s reputation when choosing how to act
truth comms relies on pressure, (stable → both benefit from truth, receiver and signaler or or when direct observation and partner-choice supplement the signals themselves) basic form → no pressure on signalers, we need to discourage lying/signal-withholding
3 Model 1 → A first pass
( 6. Effective communication definition Stable definition 7. cooperation definition, correspondence to prisoner’s dilemma 8. model description strategy / focal strategy ) ? 9. Action 10. Signal 11. Focal discriminators 12. Analysis check
- cooperative (at most e-fraction agents deflect)
- effectively comunicate
- stable
problems unpunished language unexpressed traits
4 Model 2: Next!
14 changes to address instability observers info 15 model description error numbers 1-e 1-delta 16 focal strategy analysis Thus, no matter the kind of decision, prior deviations cannot produce more beneficial future scenarios