arXiv Machine Learning

The Marked Edge Walk: A Novel MCMC Algorithm for Sampling of Graph Partitions

arXiv Machine Learning
Sep 18

Graph-Based Stochastic Power-UCT: Monte-Carlo Graph Search with Power Mean Estimation

Graph-Based Stochastic-Power-UCT (GS-Power-UCT) is a Monte‑Carlo graph search algorithm that shares states reached at the same planning depth while keeping separate values for different depths, thereby reducing duplicate simulations in stochastic MDPs. The method guarantees that, for a fixed horizon, the root estimate converges to the finite‑horizon value at an $O(n^{-1/2})$ rate, matching tree‑based Stochastic‑Power‑UCT but with improved sample reuse. Two full‑state variants—GS‑Power‑UCT‑F and GS‑Power‑UCT‑F$^+$—extend the approach to single‑node per physical state and adaptive horizons, respectively, with the latter converging to the optimal infinite‑horizon discounted value when cross‑depth bias vanishes. Experiments on stochastic planning benchmarks demonstrate that GS‑Power‑UCT outperforms both tree‑based and other graph‑based baselines in sample efficiency.

By Tung Tran, Viet Bao Mai, Hoang Ta, Tuan Dam
Hugging Face Trending Papers
Sep 17

Graph-Based Stochastic Power-UCT: Monte-Carlo Graph Search with Power Mean Estimation

The paper introduces Graph-Based Stochastic-Power-UCT (GS-Power-UCT), a Monte‑Carlo graph search algorithm that shares states reached at the same planning depth while maintaining separate values for different depths. It achieves an $O(n^{-1/2})$ convergence rate for the root estimate in finite‑horizon stochastic MDPs, matching tree‑based methods but with better sample reuse. Two full‑state variants, GS-Power-UCT‑F and GS-Power-UCT‑F$^+$, further explore sample sharing and bias control, with GS-Power-UCT‑F$^+$ converging to the optimal infinite‑horizon discounted value when the cross‑depth gap vanishes. Experiments on stochastic planning benchmarks demonstrate improved sample efficiency over existing tree‑based and graph‑based baselines.

arXiv AI
Sep 18

Reinforcement Learning for Graph Generation under a Hard Assortativity Constraint

The paper presents a reinforcement learning approach to generate graph ensembles that satisfy a hard assortativity constraint, a measure of degree–degree correlation between adjacent nodes. Unlike traditional soft-constraint methods, the learned policy performs degree-preserving rewiring to meet the exact target, reducing generation cost by at least an order of magnitude while preserving over 98% of configurational diversity. Trained on small graphs, the method generalizes to larger sizes and different topologies, allowing precise control over secondary observables such as the clustering coefficient.

By Hoyun Choi, Junghyo Jo, Deok-Sun Lee
arXiv Machine Learning
Sep 2

When Metropolis and Hastings Meet Bradley and Terry: Exact MCMC From Preference Voting

The paper introduces Pref‑MH, an exact Metropolis‑Hastings sampler that uses only stochastic binary pairwise comparisons from judges to sample from distributions conditioned on desired semantic properties. By linking the MH density ratio to the preference odds of the Bradley‑Terry model, the authors devise an accept/reject rule that guarantees convergence to the target distribution. Experiments on text, molecular, and image generation with large‑language‑model and vision‑language‑model judges show Pref‑MH as a practical, flexible method for conditional sampling when comparative feedback is readily available.

By Ariel Smogorghevski, Nir Rosenfeld, Yaniv Romano
arXiv Machine Learning
Sep 21

RheoSampling: Resolving the One-Hot Dilemma in Stochastic Dynamic-Tree Speculative Decoding

RheoSampling tackles the one‑hot dilemma in stochastic dynamic‑tree speculative decoding by decoupling token sampling from tree construction and verification. It injects a sampled token into deterministic top‑K slots, assigning distinct proxy probabilities for expansion and pruning while preserving the true sampling probability for verification, thereby achieving lossless, context‑aware top‑K construction with stochastic sampling. Experiments on various LLMs show higher acceptance rates and speedups compared to existing dynamic‑tree methods.

By Qiao Hu, Yepeng Weng, Bo Zhang, Takehisa Yairi