# Memoryless Policy Iteration for Episodic POMDPs

Source: [Memoryless Policy Iteration for Episodic POMDPs](<https://www.sota2.com/research/paper/693f96136cfd488761a81bbd>)

Collection index: [llms.txt](<https://www.sota2.com/research/llms.txt>)

Data updated: 2025-12-16T05:02:15.912Z

Authors: Roy van Zuijlen, Duarte Antunes

Published: 2025-12-11T19:54:57.000Z

## Abstract

Memoryless and finite-memory policies offer a practical alternative for solving partially observable Markov decision processes (POMDPs), as they operate directly in the output space rather than in the high-dimensional belief space. However, extending classical methods such as policy iteration to this setting remains difficult; the output process is non-Markovian, making policy-improvement steps interdependent across stages. We introduce a new family of monotonically improving policy-iteration algorithms that alternate between single-stage output-based policy improvements and policy evaluations according to a prescribed periodic pattern. We show that this family admits optimal patterns that maximize a natural computational-efficiency index, and we identify the simplest pattern with minimal period. Building on this structure, we further develop a model-free variant that estimates values from data and learns memoryless policies directly. Across several POMDPs examples, our method achieves significant computational speedups over policy-gradient baselines and recent specialized algorithms in both model-based and model-free settings.

## Recorded benchmark results

A research result applies to its stated dataset, split, metric and evaluation configuration. Compare like-for-like settings, preserve the metric's unit and direction, and distinguish paper-reported results from independent reproduction. The best result recorded here is not a claim of exhaustive, current global coverage.

- [POMDP Policy Optimization on Random POMDP](<https://www.sota2.com/research/sota/pomdp-policy-optimization-on-random-pomdp.md>): POMDP Policy Optimization; Random POMDP; L^pi: 3.2125.

## Original sources and implementation

[Original paper](<https://arxiv.org/abs/2512.11082>)

[PDF](<https://arxiv.org/pdf/2512.11082.pdf>)
