arXiv Machine Learning
Sep 24

FairTest: Search-Based Fairness Testing for Multi-Agent Reinforcement Learning Systems

FairTest is a search-based testing framework designed to uncover fairness failures in Multi-Agent Reinforcement Learning (MARL) systems. It guides candidate generation using three fitness functions—measuring observed fairness, predicting fairness from abstract states, and assessing policy decision uncertainty—and prioritizes tests based on predicted fairness and uncertainty. Evaluations on three environments and two MARL algorithms show FairTest detects significantly more fairness failures than three baselines, with a 221% increase in failure count and 23% better coverage on average.

By Xiaotong Wang, Xuan Xie
arXiv AI
Aug 25

Learning from the Test: Self-Referential Differential Testing for Deep RL Agents

The paper introduces Delta, a two‑phase framework for testing deep reinforcement learning agents. In the first phase, the agent under test is evaluated for catastrophic failures while collecting decision‑making data. The second phase trains a challenger agent from this data using offline RL; comparing the challenger’s rewards to the original agent reveals optimality bugs, and Delta successfully uncovered thousands of such issues across multiple environments.

By Junda He, Jieke Shi, Zhou Yang, Mingfei Cheng, David Lo
arXiv AI
Jun 2

LLM4Cov: Execution-Aware Agentic Learning for High-coverage Testbench Generation

arXiv:2602. 16953v3 Announce Type: replace Abstract: Execution-aware LLM agents offer a promising paradigm for learning from tool feedback, but such feedback can be expensive and slow to obtain, making online reinforcement learning (RL) less practical in certain scenarios.

By Hejia Zhang, Zhongming Yu, Chia-Tung Ho, Haoxing Ren, Brucek Khailany, Jishen Zhao
arXiv AI
Sep 23

Synthesizing Reactive Character Behaviors for Continuous Games via Programmatic Policy Search

The paper introduces a method for creating reactive character behaviors in continuous games as compact, human‑readable programs. It searches over a domain‑specific language that uses reactive geometric decisions and higher‑order constructs to discretize continuous behavior space, while eliminating redundant program forms through synthesis antipatterns. The approach, called agentic sketching, combines bottom‑up symbolic enumeration with top‑down guidance from a coding agent, and outperforms either technique alone on a benchmark of 14 continuous games.

By Maxim Gumin, Hsueh-Ti Derek Liu, Victor Zordan, Daniel Ritchie
Hugging Face Trending Papers
Sep 3

Two-Stage Reinforcement Learning for Sound and Adversarial Test Generation in Code LLMs

The paper introduces Test Cases Scaling (TCS), a two‑stage reinforcement learning framework that automatically generates sound and discriminative test cases for code‑generation large language models. Stage 1 trains a test generator to produce tests aligned with a reference solution, while Stage 2 refines the generator to produce counterexample tests that target the model’s current failure modes. Experiments on TACO and LiveCodeBench show that TCS improves pass@1 and inference‑time answer selection, and the learned generator also aids in selecting better outputs from other LLMs.