If there are two kinds of players, those who throw rock, and those who throw paper, the latter will blow the former out of the the water.
You are engaging in two fallacies: you are cherry-picking conditions to favor your particular strategy, and you are evaluating the strategies at the wrong level. Strategies should be evaluated with respect to how the affect the success of the individual person employing them, not on how they affect the success of people, in general, who employ them. This fallacy is behind much of the cooperate/one-box arguments. Sure, if everyone in Group B cooperates with other members of Group B, then Group B will do better, and on a superficial level, it seems like this means "If you're in Group B, you should cooperate with other members of Group B", but that's fallacious reasoning. It's the sort of thing that lies behind identity politics. "If Americans buy American, then Americans will do better, and you're an American, so you will benefit from buying American". Even if we grant that buying American gives a net benefit to America (which is a rather flimsy premise to begin with), it doesn't follow that any American has a rational reason to buy American. In your scenario, the presence of people with the "cooperate with people who have a reputation greater than 0" provides a reason to cooperate in the first round, but there is no reason whatsoever to condition cooperation on someone having a reputation greater than 0. Anyone who, in this scenario, thinks that one should cooperate with people with reputation greater than 0 does indeed not understand game theory.
You are engaging in two fallacies: you are cherry-picking conditions to favor your particular strategy, and you are evaluating the strategies at the wrong level.
No, I'm simplifying for arguments' sake, using the example given by Alex (cooperating with any positive reputation). I discuss more complex strategies elsewhere in the thread, of course "cooperate only with people with > 0 reputation is a pretty stupid and exploitable strategy, my point is that even such a stupid strategy could beat Alex's "always defect".
TL;DR = write a python script to win this applied game theory contest for $1000. Based on Prisoner's Dilemma / Tragedy of the Commons but with a few twists. Deadline Sunday August 18.
https://brilliant.org/competitions/hunger-games/rules/
The choices are H = hunt (cooperate) and S = slack (defect), and they use confusing wording here, but as far as I can tell the payoff matrix is (in units of food)
What's interesting is you don't get the entirety of your partner's history (so strategies like Tit-Tit-Tit for Tat don't work) instead you get only their reputation, which is the fraction of times they've hunted.
To further complicate the Nash equilibria, there's the option to overhunt: a random number m, 0 < m < P(P−1) is chosen before each round (round consisting of P−1 hunts, remember) and if the total number of hunt-choices is at least m, then each player is awarded 2(P−1) food units (2 per hunt).
Your python program has to decide at the start of each round whether or not to hunt with each opponent, based on: