4 ms·
It's not crucial that you meet the same partner (opponent) again. It's enough for you to be in a population where there is a good chance that the partner will
by adrianratnapala 9y ago
It's not crucial that you meet the same partner (opponent) again. It's enough for you to be in a population where there is a good chance that the partner will cooperate if you do. For some definition of "good chance" the right strategy is to try to cooperate yourself and then fall back on something else if it fails.
And this is interesting because it gives us a toy model of moralistic "Do unto others" (as opposed to rational exchange).
- tedsanders 9y agoCan you explain why cooperation still works when you don't repeat partners? (Assuming I've interpreted you correctly.) The reason cooperative strategies can work is that actions depend on previous actions. If you are not meeting the same partner, then your partner's actions will not depend on your previous actions, and you will always do better by defecting.
- adrianratnapala 9y agoNow that I think about it, you are right that for PD, there has to be some one-on-one iteration too. I think my automatic mental model was that agents came together and played a few rounds with one partner, and then switch to some other partner. In this case you can afford to be nice in the first round, and then cut your losses. But even that strategy is only optimal if most of the rest of the community is nice in the first round too. If it is full of defectors, then you should defect in the first round too.
- neilwilson 9y agoYour partners talk to each other. The problem with all economic simulations is that they assume extreme individualisation. Because that is what they want the world to be like. In reality the world is a network. Reputation matters.