Policy learning “without” overlap: Pessimism and generalized empirical Bernstein’s inequality
“无需”统一重叠的策略学习:悲观原则与广义经验 Bernstein 不等式
This paper studies offline policy learning, which aims at utilizing observations collected a priori (from either fixed or adaptively evolving behavior policies) to learn an optimal individualized decision rule that achieves the best overall outcomes for a given population. Existing policy learning methods rely on a uniform overlap assumption, that is, the propensities of exploring all actions for all individual characteristics must be lower bounded; the performance of the…