# Logically-Constrained Neural Fitted Q-Iteration

arXiv: https://arxiv.org/abs/1809.07823 · HTML: https://mlsanity.com/paper/1809.07823/

## Key facts

- Cited by 17 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 20 Sep 2018.

## Built on by (most cited first, 17 of 17)

- [Evaluating Cognitive Maps and Planning in Large Language Models with CogEval](https://mlsanity.com/paper/2309.15129/) (2023)
- [Modular Deep Reinforcement Learning for Continuous Motion Planning with Temporal Logic](https://mlsanity.com/paper/2102.12855/) (2021)
- [Multi-Agent Reinforcement Learning with Temporal Logic Specifications](https://mlsanity.com/paper/2102.00582/) (2021)
- [Active Task-Inference-Guided Deep Inverse Reinforcement Learning](https://mlsanity.com/paper/2001.09227/) (2020)
- [ALLURE: Auditing and Improving LLM-based Evaluation of Text using Iterative In-Context-Learning](https://mlsanity.com/paper/2309.13701/) (2023)
- [LCRL: Certified Policy Synthesis via Logically-Constrained Reinforcement Learning](https://mlsanity.com/paper/2209.10341/) (2022)
- [Online Learning of Non-Markovian Reward Models](https://mlsanity.com/paper/2009.12600/) (2020)
- [Programmatic Reward Design by Example](https://mlsanity.com/paper/2112.08438/) (2021)
- [A Hierarchical Bayesian Approach to Inverse Reinforcement Learning with Symbolic Reward Machines](https://mlsanity.com/paper/2204.09772/) (2022)
- [Accelerated Reinforcement Learning for Temporal Logic Control Objectives](https://mlsanity.com/paper/2205.04424/) (2022)
- [Verified Probabilistic Policies for Deep Reinforcement Learning](https://mlsanity.com/paper/2201.03698/) (2022)
- [Reinforcement Learning Guided by Provable Normative Compliance](https://mlsanity.com/paper/2203.16275/) (2022)
- [Data-Driven Abstractions via Binary-Tree Gaussian Processes for Formal Verification](https://mlsanity.com/paper/2407.21029/) (2024)
- [System III: Learning with Domain Knowledge for Safety Constraints](https://mlsanity.com/paper/2304.11593/) (2023)
- [Safeguarded Progress in Reinforcement Learning: Safe Bayesian Exploration for Control Policy Synthesis](https://mlsanity.com/paper/2312.11314/) (2023)
- [Progressive Safeguards for Safe and Model-Agnostic Reinforcement Learning](https://mlsanity.com/paper/2410.24096/) (2024)
- [Value Functions as Supermartingale Certificates](https://mlsanity.com/paper/2605.31524/) (2026)

## Abstract (arXiv)

We propose a method for efficient training of Q-functions for continuous-state Markov Decision Processes (MDPs) such that the traces of the resulting policies satisfy a given Linear Temporal Logic (LTL) property. LTL, a modal logic, can express a wide range of time-dependent logical properties (including "safety") that are quite similar to patterns in natural language. We convert the LTL property into a limit deterministic Buchi automaton and construct an on-the-fly synchronised product MDP. The control policy is then synthesised by defining an adaptive reward function and by applying a modified neural fitted Q-iteration algorithm to the synchronised structure, assuming that no prior knowledge is available from the original MDP. The proposed method is evaluated in a numerical study to test the quality of the generated control policy and is compared with conventional methods for policy synthesis such as MDP abstraction (Voronoi quantizer) and approximate dynamic programming (fitted value iteration).
