PSYCH 3F03 Lecture Notes - Lecture 6: Evolutionarily Stable Strategy, Cassava, Public Goods Game
Document Summary
Cooperation expect repayment from non-kin, but not kin. Short term benefit v and short term cost k to the actor: v k = - c. 2 individuals with a common resource, and can either contribute to or extract from. It costs you to make a contribution: doing something that benefits others, when there is no real policing to force you to contribute, a(cid:374)d you do(cid:374)"t ha(cid:448)e to (cid:272)o(cid:374)tri(cid:271)ute to receive the benefits. Snowdrift game: trapped in your car, someone is stuck behind you. You can 1) cooperate to dig yourself out, freeing both cars or 2) defect, sit and wait: mixed evolutionarily stable state both strategies can invade when rare, a mixture of the two strategies is stable. As the cost for volunteering increases, the frequency of cooperation decreases: as the benefit for cooperating increases, more individuals will evolve to cooperate. Something too difficult to do on your own if we work together we can split the rewards.