arXiv Machine Learning

Controlled Acquisition and Abstention in Three-Channel Score Conflicts

The paper introduces a controlled benchmark for deciding whether to acquire a third modality or abstain when audio, video, and text scores conflict. A threshold policy that observes two signed scores can request the third at a cost and abstain, achieving higher targeted decision accuracy and utility than always-answer fusion under certain reward settings. Experiments on synthetic and real data show that the policy’s advantage depends on the ambiguity mechanism, budget constraints, and the ranking of observed pairs, highlighting the trade‑off between full-modality accuracy and pre‑request selection value.

arXiv Machine Learning
Sep 15

The Limits of Reference-Free Speech Quality Metrics as Evaluators and Rewards on Modern Text-to-Speech

arXiv:2609.13150v1 Announce Type: cross Abstract: Reference-free quality predictors such as UTMOS, DNSMOS and SCOREQ are the de facto automatic evaluators for text-to-speech (TTS) and are increasingl...

By Antonis Asonitis, Juan Pablo Zuluaga Gomez, Francesco Verdini, Aref Farhadipour, Marzieh Razavi, Pierre-Edouard Honnet, Vijeta Avijeet
arXiv AI
Sep 30

Can a Cacheable Decision Model Follow Rules?

The paper evaluates Certo, a small non‑generative decision model that scores candidate actions based on text. It compares a joint scorer that processes state, rules, and candidates together with a cacheable encoder that pre‑encodes candidates to reduce cost. Experiments show the cacheable approach loses rule sensitivity, while targeted counterfactual supervision can recover performance on synthetic tasks; however, on real rules the joint scorer still outperforms the cacheable version, and cross‑domain mixtures do not improve accuracy.

By Dushyant Rajput (AltSlate Labs LLP), Nirdesh Chauhan (AltSlate Labs LLP), Siddharth Kosaraju (AltSlate Labs LLP)
arXiv AI
Sep 18

The Missing Complement: State-Conditioned Minimal Sufficient Evidence for Coding Agents

The paper introduces State‑Conditioned Minimal Sufficient Evidence Recovery (SER), a method that, given a coding agent’s current state, reconstructs a compact set of evidence passages that collectively provide all facts needed for the agent’s next decision. Using the SERBench dataset of 500 held‑out states from 45 repositories, the authors show that their MSS‑Complement approach recovers a complete evidence set for 73.0 % of states with five items and 80.6 % with eight, outperforming baseline ranking methods. The study also demonstrates that this set‑level policy improves downstream performance on AMA‑Bench and highlights the importance of retrieving missing facts rather than merely re‑ranking similar passages.

By Zhexi Feng, Ruiyi Zhang, Yongbo Yang, Pengtao Xie
arXiv AI
Oct 16

Verdict: Encode Once, Decide Many

Verdict-MQ is an open encoder that processes a single piece of state once and then answers multiple typed questions about that state, avoiding separate passes for each question. By using a structured attention mask, it ensures the state encoding is independent of question order and prevents questions from influencing one another. On the typed‑decisions benchmark, Verdict‑MQ outperforms a larger specialist model, achieving higher accuracy and better calibration, while on other benchmarks it shows mixed results compared to fine‑tuned baselines.

By Avdhesh Singh Chouhan, Jack Perry
arXiv Machine Learning
Oct 2

Uncertainty-Normalized Margins for Direct Preference Optimization

The paper introduces Uncertainty‑Normalized Margin DPO (UNM‑DPO), a method that augments direct preference optimization with strength‑dependent margins and a learned prompt scale derived from a heteroskedastic Bradley‑Terry model. Two training objectives—advantage‑only (AO) and whole‑residual (WR)—compare implicit rewards from response log‑probability ratios, with WR enabling identification of the prompt scale and a practical learning procedure. Building on WR, ULNM‑DPO‑WR further normalizes rewards by response length, and experiments on HelpSteer2/3 and AlpacaEval show higher win rates, mean rewards, and shorter responses compared to baseline DPO and SimPO.

By Sadegh Khorasani, Petrus Mikkola, Matthias Grossglauser
arXiv AI
Aug 21

Credit Without Ground Truth: Auditing Step-Level Credit Assignment in LLM Agents Against Executed Replay

arXiv:2608. 19760v1 Announce Type: cross Abstract: Audited against causal ground truth from executed replay in a single-agent tool environment (ALFWorld), none of the step-level credit signals used to train LLM agents -- LLM-judge scores, outcome-conditioned logprob ratios, or the policy's own confidence -- identifies which steps causally matter better than chance.

By Haiyue Zhang