Title
A Formal Solution to the Grain of Truth Problem.
Abstract
A Bayesian agent acting in a multi-agent environment learns to predict the other agentsu0027 policies if its prior assigns positive probability to them (in other words, its prior contains a grain of truth). Finding a reasonably large class of policies that contains the Bayes-optimal policies with respect to this class is known as the grain of truth problem. Only small classes are known to have a grain of truth and the literature contains several related impossibility results. In this paper we present a formal and general solution to the full grain of truth problem: we construct a class of policies that contains all computable policies as well as Bayes-optimal policies for every lower semicomputable prior over the class. When the environment is unknown, Bayes-optimal agents may fail to act optimally even asymptotically. However, agents based on Thompson sampling converge to play e-Nash equilibria in arbitrary unknown computable multi-agent environments. While these results are purely theoretical, we show that they can be computationally approximated arbitrarily closely.
Year
Venue
DocType
2016
UAI
Journal
Volume
Citations 
PageRank 
abs/1609.05058
2
0.37
References 
Authors
10
3
Name
Order
Citations
PageRank
Jan Leike115015.49
Jessica Taylor230.71
Benya Fallenstein320.37