arXiv AI

Evaluating Exact Output and Checkpoint-State Prediction in Real Programs

The paper introduces a benchmark for predicting a program’s final output and checkpoint state using only its source code and input, extending CRUXEval-style tasks with both short‑ and long‑trace inputs and checkpoints inside and after loops. It evaluates 400 cases from 371 Python and C++ programs across seven settings from four model families, achieving up to 93.0% accuracy on short‑trace final output and 77.0% on long‑trace final output, with reasoning‑enabled settings outperforming non‑reasoning ones by 33.1 to 55.2 percentage points. The study also shows that longer‑trace inputs can change correctness outcomes and that the benchmark reveals errors that short‑output scores alone would miss.

arXiv Machine Learning
Oct 28

Checkpoint Reload Explains Most of the Measured State Gap in Two State Discovery Reproductions

The paper investigates whether the latent states reconstructed during inference match those stored during training in temporal models, focusing on State Discovery in World Machine. By comparing stored state tables with rollouts from the best‑validation checkpoint and the last‑epoch weights, the authors find that reloading the checkpoint used to write the table eliminates 90–91% of the mean per‑dimension Wasserstein‑1 distance, explaining most of the observed state gap. Causal distillation and frozen SD updates fail to meet their criteria under either checkpoint.

By Weijia Han, Lisha Qu
arXiv Machine Learning
Sep 29

Decodable In-Context State and Model Output Across Training

The paper investigates how a probe can decode in‑context bindings on model errors and how probe‑guided steering can repair them. It tracks probe accuracy, model output, and steering response across public pretraining and post‑training checkpoints, noting that probe accuracy improves during Pythia pretraining and that steering benefits grow with model size. The study also shows that decoders trained on final state or candidate logits do not outperform each other on late‑checkpoint errors, and presents an information‑theoretic counterexample explaining why decodability on errors alone cannot prove discarded output information.

By Manas Venkata Sai Ravulapalli, Samrath Singh Chadha
arXiv AI
Oct 15

Long-Horizon-Terminal-Bench 2.0: Automating Diverse Task Construction and Measuring Sustained Agent Progress

arXiv:2610.14146v1 Announce Type: new Abstract: Long-horizon terminal benchmarks measure whether an agent can sustain progress through extended workflows with process rewards, not only whether its fi...

By Zongxia Li, Zhongzhi Li, Yucheng Shi, Ruhan Wang, Junyao Yang, Chengsong Huang, Zhichao Liu, Xiyang Wu, Anhao Li, Yue Yu, Ergan Shang, Fuxiao Liu, Tong Zheng, Ninghao Liu, Lichao Sun, Haitao Mi, Leowei Liang
arXiv Machine Learning
Oct 16

Effectiveness of Hidden-State Probes for Localizing Reasoning Failures

The paper investigates whether hidden-state probes can identify the type of reasoning failure and the specific step that causes it in large language models. By comparing probes trained on final-answer correctness with those trained using Monte Carlo rollouts, the authors find that standard probes miss a large proportion of recoverable failures and that probe performance depends heavily on training design. Across 4B and 8B models, no probe outperforms a simple rule based on trace length for locating the failing step.

By Shubham Subhnil, Yannis Belkhiter, Erik Miehling, Adam Dahlgren Lindstr\"om, Elizabeth M. Daly
arXiv AI
Oct 12

ReplaySSM: Cache SSM Inputs, Not State

ReplaySSM is a technique that redefines how state-space models (SSMs) handle their recurrent state by caching SSM inputs instead of the state itself. It unrolls the recurrence into a checkpoint plus a buffer of recent inputs, reducing state memory traffic by about half and enabling efficient speculative rollback. The method also allows separate precision levels for checkpoints, improving output accuracy while accelerating decoding in hybrid models such as Mamba-2 and Gated DeltaNet.

By Ze-Wei Liou, Harris Nover, Amey Naik, Andrii Skliar, Igor Shovkun, Ido Shahaf, Tri Dao
arXiv Computation and Language
Sep 28

TRACE: Temporal Audit and Condition-aware Evaluation of Streaming Video Understanding

TRACE (Temporal Audit and Condition-aware Evaluation) is a new benchmark and evaluation framework for streaming video understanding that explicitly records when evidence becomes valid, how visual history is maintained, and how responses are triggered. It combines temporally audited visual tasks, evidence timing, instruction-dependent trigger annotations, a unified causal Core–Adapter protocol, and multidimensional reporting of answer quality, timeliness, response-selection behavior, workload, completion, and reliability. Using 1,240 records from 517 videos, TRACE evaluated eight publicly available models in eight configurations, revealing that similar QA accuracy can hide significant differences in completion, answer validity, generation workload, and proactive performance metrics such as response delay, false alarms, and missed target windows.

By Yibo Ma, Qianqian Zhang, Peng Liu, Tiancheng Zhao