Pessimistic Iterative Planning for Robust POMDPs
- URL: http://arxiv.org/abs/2408.08770v3
- Date: Tue, 12 Nov 2024 13:50:05 GMT
- Title: Pessimistic Iterative Planning for Robust POMDPs
- Authors: Maris F. L. Galesloot, Marnix Suilen, Thiago D. Simão, Steven Carr, Matthijs T. J. Spaan, Ufuk Topcu, Nils Jansen,
- Abstract summary: We propose a pessimistic iterative planning (PIP) framework to compute robust memory-based POMDP policies.
Within PIP, we propose the rFSCNet algorithm, which finds an FSC through a recurrent neural network by using supervision policies optimized for the pessimistic POMDP.
In each iteration, rFSCNet finds an FSC through a recurrent neural network by using supervision policies optimized for the pessimistic POMDP.
- Score: 33.73695799565586
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Robust POMDPs extend classical POMDPs to handle model uncertainty. Specifically, robust POMDPs exhibit so-called uncertainty sets on the transition and observation models, effectively defining ranges of probabilities. Policies for robust POMDPs must be (1) memory-based to account for partial observability and (2) robust against model uncertainty to account for the worst-case instances from the uncertainty sets. To compute such robust memory-based policies, we propose the pessimistic iterative planning (PIP) framework, which alternates between two main steps: (1) selecting a pessimistic (non-robust) POMDP via worst-case probability instances from the uncertainty sets; and (2) computing a finite-state controller (FSC) for this pessimistic POMDP. We evaluate the performance of this FSC on the original robust POMDP and use this evaluation in step (1) to select the next pessimistic POMDP. Within PIP, we propose the rFSCNet algorithm. In each iteration, rFSCNet finds an FSC through a recurrent neural network by using supervision policies optimized for the pessimistic POMDP. The empirical evaluation in four benchmark environments showcases improved robustness against several baseline methods and competitive performance compared to a state-of-the-art robust POMDP solver.
Related papers
- On the Plasticity and Stability for Post-Training Large Language Models [54.757672540381236]
We identify a root cause as the conflict between plasticity and stability gradients.<n>We propose Probabilistic Conflict Resolution (PCR), a framework that models gradients as random variables.<n>PCR significantly smooths the training trajectory and achieves superior performance in various reasoning tasks.
arXiv Detail & Related papers (2026-02-06T07:31:26Z) - Rethinking the Trust Region in LLM Reinforcement Learning [72.25890308541334]
Proximal Policy Optimization (PPO) serves as the de facto standard algorithm for Large Language Models (LLMs)<n>We propose Divergence Proximal Policy Optimization (DPPO), which substitutes clipping with a more principled constraint.<n>DPPO achieves superior training and efficiency compared to existing methods, offering a more robust foundation for RL-based fine-tuning.
arXiv Detail & Related papers (2026-02-04T18:59:04Z) - Constrained and Robust Policy Synthesis with Satisfiability-Modulo-Probabilistic-Model-Checking [4.064849471241967]
This paper contributes the first approach to effectively compute robust policies subject to arbitrary structural constraints.<n> Experiments on a few hundred benchmarks demonstrate the feasibility for constrained and robust policy synthesis.
arXiv Detail & Related papers (2025-11-11T10:28:42Z) - Best-Effort Policies for Robust Markov Decision Processes [69.60742680559788]
We study the common generalization of Markov decision processes (MDPs) with sets of transition probabilities, known as robust MDPs (RMDPs)<n>We call such a policy an optimal robust best-effort (ORBE) policy.<n>We prove that ORBE policies always exist, characterize their structure, and present an algorithm to compute them with a small overhead compared to standard robust value iteration.
arXiv Detail & Related papers (2025-08-11T09:18:34Z) - Sequential Monte Carlo for Policy Optimization in Continuous POMDPs [9.690099639375456]
We introduce a novel policy optimization framework for continuous partially observable Markov decision processes (POMDPs)<n>Our method casts policy learning as probabilistic inference in a non-Markovian Feynman--Kac model.<n>We demonstrate the effectiveness of our algorithm across standard continuous POMDP benchmarks.
arXiv Detail & Related papers (2025-05-22T14:45:46Z) - Robust Finite-Memory Policy Gradients for Hidden-Model POMDPs [7.447371788025412]
A policy is robust for a given HM-POMDP if it achieves sufficient performance for each of its POMDPs.<n>We show that our approach produces policies that are more robust and generalize better to unseen POMDPs.
arXiv Detail & Related papers (2025-05-14T16:15:58Z) - Efficient Learning of POMDPs with Known Observation Model in Average-Reward Setting [56.92178753201331]
We propose the Observation-Aware Spectral (OAS) estimation technique, which enables the POMDP parameters to be learned from samples collected using a belief-based policy.
We show the consistency of the OAS procedure, and we prove a regret guarantee of order $mathcalO(sqrtT log(T)$ for the proposed OAS-UCRL algorithm.
arXiv Detail & Related papers (2024-10-02T08:46:34Z) - Monte Carlo Planning for Stochastic Control on Constrained Markov Decision Processes [1.445706856497821]
This work defines an MDP framework, the textttSD-MDP, where we disentangle the causal structure of MDPs' transition and reward dynamics.
We derive theoretical guarantees on the estimation error of the value function under an optimal policy by allowing independent value estimation from Monte Carlo sampling.
arXiv Detail & Related papers (2024-06-23T16:22:40Z) - Recursively-Constrained Partially Observable Markov Decision Processes [13.8724466775267]
We show that C-POMDPs violate the optimal substructure property over successive decision steps.
Online re-planning in C-POMDPs is often ineffective due to the inconsistency resulting from this violation.
We introduce the Recursively-Constrained POMDP, which imposes additional history-dependent cost constraints on the C-POMDP.
arXiv Detail & Related papers (2023-10-15T00:25:07Z) - Provably Efficient UCB-type Algorithms For Learning Predictive State
Representations [55.00359893021461]
The sequential decision-making problem is statistically learnable if it admits a low-rank structure modeled by predictive state representations (PSRs)
This paper proposes the first known UCB-type approach for PSRs, featuring a novel bonus term that upper bounds the total variation distance between the estimated and true models.
In contrast to existing approaches for PSRs, our UCB-type algorithms enjoy computational tractability, last-iterate guaranteed near-optimal policy, and guaranteed model accuracy.
arXiv Detail & Related papers (2023-07-01T18:35:21Z) - Fine-Tuning Language Models with Advantage-Induced Policy Alignment [80.96507425217472]
We propose a novel algorithm for aligning large language models to human preferences.
We show that it consistently outperforms PPO in language tasks by a large margin.
We also provide a theoretical justification supporting the design of our loss function.
arXiv Detail & Related papers (2023-06-04T01:59:40Z) - Double Pessimism is Provably Efficient for Distributionally Robust
Offline Reinforcement Learning: Generic Algorithm and Robust Partial Coverage [15.858892479232656]
We study robust offline reinforcement learning (robust offline RL)
We propose a generic algorithm framework called Doubly Pessimistic Model-based Policy Optimization ($P2MPO$)
We show that $P2MPO$ enjoys a $tildemathcalO(n-1/2)$ convergence rate, where $n$ is the dataset size.
arXiv Detail & Related papers (2023-05-16T17:58:05Z) - Optimality Guarantees for Particle Belief Approximation of POMDPs [55.83001584645448]
Partially observable Markov decision processes (POMDPs) provide a flexible representation for real-world decision and control problems.
POMDPs are notoriously difficult to solve, especially when the state and observation spaces are continuous or hybrid.
We propose a theory characterizing the approximation error of the particle filtering techniques that these algorithms use.
arXiv Detail & Related papers (2022-10-10T21:11:55Z) - Robust Anytime Learning of Markov Decision Processes [8.799182983019557]
In data-driven applications, deriving precise probabilities from limited data introduces statistical errors.
Uncertain MDPs (uMDPs) do not require precise probabilities but instead use so-called uncertainty sets in the transitions.
We propose a robust anytime-learning approach that combines a dedicated Bayesian inference scheme with the computation of robust policies.
arXiv Detail & Related papers (2022-05-31T14:29:55Z) - Robust Entropy-regularized Markov Decision Processes [23.719568076996662]
We study a robust version of the ER-MDP model, where the optimal policies are required to be robust.
We show that essential properties that hold for the non-robust ER-MDP and robust unregularized MDP models also hold in our settings.
We show how our framework and results can be integrated into different algorithmic schemes including value or (modified) policy.
arXiv Detail & Related papers (2021-12-31T09:50:46Z) - Risk-Averse Decision Making Under Uncertainty [18.467950783426947]
A large class of decision making under uncertainty problems can be described via Markov decision processes (MDPs) or partially observable MDPs (POMDPs)
In this paper, we consider the problem of designing policies for MDPs and POMDPs with objectives and constraints in terms of dynamic coherent risk measures.
arXiv Detail & Related papers (2021-09-09T07:52:35Z) - Rule-based Shielding for Partially Observable Monte-Carlo Planning [78.05638156687343]
We propose two contributions to Partially Observable Monte-Carlo Planning (POMCP)
The first is a method for identifying unexpected actions selected by POMCP with respect to expert prior knowledge of the task.
The second is a shielding approach that prevents POMCP from selecting unexpected actions.
We evaluate our approach on Tiger, a standard benchmark for POMDPs, and a real-world problem related to velocity regulation in mobile robot navigation.
arXiv Detail & Related papers (2021-04-28T14:23:38Z) - Efficient semidefinite-programming-based inference for binary and
multi-class MRFs [83.09715052229782]
We propose an efficient method for computing the partition function or MAP estimate in a pairwise MRF.
We extend semidefinite relaxations from the typical binary MRF to the full multi-class setting, and develop a compact semidefinite relaxation that can again be solved efficiently using the solver.
arXiv Detail & Related papers (2020-12-04T15:36:29Z) - Near Optimality of Finite Memory Feedback Policies in Partially Observed
Markov Decision Processes [0.0]
We study a planning problem for POMDPs where the system dynamics and measurement channel model is assumed to be known.
We find optimal policies for the approximate belief model under mild non-linear filter stability conditions.
We also establish a rate of convergence result which relates the finite window memory size and the approximation error bound.
arXiv Detail & Related papers (2020-10-15T00:37:51Z) - Exploiting Submodular Value Functions For Scaling Up Active Perception [60.81276437097671]
In active perception tasks, agent aims to select sensory actions that reduce uncertainty about one or more hidden variables.
Partially observable Markov decision processes (POMDPs) provide a natural model for such problems.
As the number of sensors available to the agent grows, the computational cost of POMDP planning grows exponentially.
arXiv Detail & Related papers (2020-09-21T09:11:36Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.