Vaniver comments on Open thread, Mar. 2 - Mar. 8, 2015 - Less Wrong Discussion
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I think I've found the core of our disagreement. I want an algorithm that considers all possible paths through time. It decides on a set of actions, not just for the current time step, but for all possible future time steps. It chooses such that the final probability distribution of possible outcomes, at some point in the future, is optimal according to some metric. I originally thought of median, but it can work with any arbitrary metric.
This is a generalization of expected utility. The VNM axioms require an algorithm to make decisions independently and Just In Time. Whereas this method lets it consider all possible outcomes. It may be less elegant than EU, but I think it's closer to what humans actually want.
Anyway your example is wrong, even without predetermined actions. The algorithm would buy bet A, but then not buy bet B. This is because it doesn't consider bets in isolation like EU, but considers it's entire probability distribution of possible outcomes. Buying bet B would decrease it's expected median utility, so it wouldn't take it.
So, I think you might be interested in UDT. (I'm not sure what the current best reference for that is.) I think that this requires actual omniscience, and so is not a good place to look for decision algorithms.
(Though I should add that typically utilities are defined over world-histories, and so any decision algorithm typically identifies classes of 'equivalent' actions, i.e. acknowledges that this is a thing that needs to be accepted somehow.)
UDT is overkill. The idea that all future choices can be collapsed into a single choice appears in the work of von Neumann and Morgenstern, but is probably much older.