Quasi-Deterministic Partially Observable Markov Decision Processes

We study a subclass of POMDPs, called quasi-deterministic POMDPs (QDET-POMDPs), characterized by deterministic actions and stochastic observations. While this framework does not model the same general problems as POMDPs, they still capture a number of interesting and challenging problems and, in some cases, have interesting properties. By studying the observability available in this subclass, we show that QDET-POMDPs may fall many steps in the complexity classes of polynomial hierarchy.