If there’s a population of mostly TDT/UDT agents and few CDT agents (and nobody knows who the CDT agents are) and they’re randomly paired up to play one-shot PD, then the CDT agents do better. What does this imply?
the CDT agents don’t necessarily do better. e.g., if “not being tied for first” means “the CDT agents accrue an advantage, use that advantage to gain further advantage after the game, and eventually take over the world”, then the TDT/UDT agents all choose to defect because of the presence of CDT agents, and the CDT agents also all defect because of their decision theory.
wheras if there’s no real cost to not being first, then there’s a couple possibilities i see. (a) the TDT/UDT agents all defect in order to discourage the existence of CDT agents. (b) the TDT/UDT agents cooperate, and the CDT agents do perform better. i think (a) would be done in worlds/situations where it would work, but (b) is what happens in, e.g., a truly one-shot prisoners dilemma that’s the only thing that will ever exist, and afterwards all the agents cease to exist, for example.
“what does this imply”—maybe we can conclude there is no decision algorithm which is necessarily best in all possible situations/worlds, and that one of the main things ‘how well a decision algorithm performs’ depends on is what decision algorithms other agents are using.
(meta p.s: i’d appreciate feedback on whether this comment was insightful to you)
the CDT agents don’t necessarily do better. e.g., if “not being tied for first” means “the CDT agents accrue an advantage, use that advantage to gain further advantage after the game, and eventually take over the world”, then the TDT/UDT agents all choose to defect because of the presence of CDT agents, and the CDT agents also all defect because of their decision theory.
wheras if there’s no real cost to not being first, then there’s a couple possibilities i see. (a) the TDT/UDT agents all defect in order to discourage the existence of CDT agents. (b) the TDT/UDT agents cooperate, and the CDT agents do perform better. i think (a) would be done in worlds/situations where it would work, but (b) is what happens in, e.g., a truly one-shot prisoners dilemma that’s the only thing that will ever exist, and afterwards all the agents cease to exist, for example.
“what does this imply”—maybe we can conclude there is no decision algorithm which is necessarily best in all possible situations/worlds, and that one of the main things ‘how well a decision algorithm performs’ depends on is what decision algorithms other agents are using.
(meta p.s: i’d appreciate feedback on whether this comment was insightful to you)