Publications

Simplifying the Modeling of Arbitrary Conditionals in Natural Language
Causal Transformers model sequences through an autoregressive factorization of the joint distribution, which enables efficient left-to-right… (see more) decoding and conditional likelihood computation. However, they cannot tractably sample from or evaluate arbitrary conditionals -- e.g., a block of text conditioned on past and future tokens. Recent work aims to solve this problem through novel architectures, but they often lead to sub-optimal modeling of such conditionals and degraded generations. We propose Arbitrary Conditionals GPT (AC-GPT) which introduces a simple modification to standard causal Transformers to enable evaluating and sampling from arbitrary conditionals -- including past, future, and mixed contexts -- within a single forward pass. Unlike prior approaches, our method preserves the standard left-to-right ordering and next-token prediction objective essential for both strong performance and efficient training on natural language. Crucially, this compatibility allows existing LLMs to be fine-tuned for arbitrary conditioning. Our empirical results indicate that our method outperforms baselines on modeling arbitrary conditionals, without degrading standard left-to-right performance.
AgentBeats: Agentifying Agent Assessment for Openness, Standardization, and Reproducibility
Xiaoyuan Liu
Jianhong Tu
Yuqi Chen
Siyuan Xie
Sihan Ren
Tianneng Shi
Gal Gantar
Evan Sandoval
D Lee
Daniel Miao
Peter J. Gilbert
Nick Hynes
Mauro Staver
Warren He
David Marn
Andrew Low
Xi Zhang
Elron Bandel
Michal Shmueli-Scheuer
Somasekhar Reddy … (see 9 more)
Alexandre Lacoste
R Radha Krishnan
Elham Tabassi
Yu Su
Victor Barres
Chenguang Wang
Wenbo Guo
Dawn Song
Agent systems are advancing quickly across domains, but their evaluation remains fragmented. Most benchmarks rely on fixed, LLM-centric harn… (see more)esses that require heavy integration, create test-production mismatch, and limit fair comparison across diverse agent designs. The root problem is the lack of an open, agent-agnostic assessment interface. We advocate Agentified Agent Assessment (AAA), where evaluation is performed by judge agents and all participants interact through standardized protocols: A2A for task management and MCP for tool access. Conventional benchmarking defines two separate interfaces, one for the benchmark and one for the agent, while AAA only needs one; this yields a generic, unified framework that separates assessment logic from agent implementation and enables reproducible, interoperable, and multi-agent evaluation. We further introduce AgentBeats as a concrete realization of AAA: we identify five practical operation modes that make standardized assessment compatible with real-world constraints on openness, privacy, and reproducibility. To evaluate our design at scale, we conduct two studies: a five-month open competition that drew 298 judge agents across 12 categories together with 467 subject agents from independent participants, showing that AAA applies across a heterogeneous range of benchmarks; and a case study on coding agents that confirms agentified evaluation preserves fidelity with the public record while surfacing previously missing head-to-head results, yielding research insights about agent design. Combining a community-scale field study and a controlled coding case study, we verify that AAA delivers coverage, practicality, and fidelity across heterogeneous scenarios at scale. Together, AAA and AgentBeats offer a clear path toward open, standardized, and reproducible agent assessment.
Data-Driven Stochastic Vehicle Routing Problems with Deadlines Under Decision-Dependent Travel Time
Shanshan Wang
Leandro C. Coelho
Problem definition: Vehicle routing problems (VRPs) with deadlines have received significant attention around the world. Motivated by a real… (see more)-world food delivery problem, we assume that the travel time depends on the routing decisions, and we study a data-driven stochastic VRP with deadlines and endogenous uncertainty. Methodology/results: We use the nonparametric approaches, including k-nearest neighbor (kNN) and kernel density estimation (KDE), to estimate the decision-dependent probability distribution of travel time. To solve the resulting problem efficiently, we employ a logic-based Benders decomposition (LBBD) algorithm with several algorithmic enhancements. In particular, we propose a novel family of optimality cuts that includes the expected delay for all the subroutes. Moreover, we solve a total travel cost minimization problem to warm start the algorithm. We also use a local search procedure to improve the current routing decision and propose a machine learning–based lower bound heuristic to efficiently solve problems of realistic size. A practical case study for a food delivery routing problem using real-world data is conducted to show the efficiency of the proposed techniques and the advantage of the data-driven stochastic VRP in reducing the expected delay. Managerial implications: In our case study, we show that incorporating routing decisions into a nonparametric model outperforms a state-of-the-art data-driven parametric model by 23% on average in terms of the expected delay and the order-assignment decisions obtained from a robust model with travel-time predictors by 26% on average. Moreover, compared with the drivers’ actual routes and arc-based VRP models that ignore the endogenous uncertainty, our suggested routes can significantly improve the on-time performance of delivery services. We also quantify the value of the proposed routes with different service deadlines. Funding: S. Wang was partially supported by the Natural Sciences and Engineering Research Council of Canada [Grant RGPIN-2016-05208], IVADO, and a joint project between the Fonds de Recherche du Québec - Société et Culture (FRQSC) and the National Natural Science Foundation of China (NSFC) [Grant 295837]. She is also most recently supported by the National Natural Science Foundation of China [Grants 72501014, 72371022, and 72272014]. Supplemental Material: The online appendix is available at https://doi.org/10.1287/msom.2024.0899 .
Feature Geometry of Language Models Transfer Across Modalities to Time Series
Language models transfer to time-series forecasting, but it is unclear whether this reflects reusable internal structure or rapid relearning… (see more) under a familiar architecture. We study this transfer directly by comparing pretrained and randomly initialized versions of the same model on a forecasting objective whose inputs have little semantic overlap with text but still require autoregressive sequential structure. Across Qwen3-0.6B finetuning experiments, language initialization gives coherent per-example gradients from the first update, while random initialization first passes through a low-alignment warmup phase. Effective-rank and hidden-state analyses show that finetuning selectively reshapes an existing representation geometry rather than constructing the simpler temporal geometry found by models trained from scratch. Cross-domain sparse features and causal ablations then expose candidate transferred primitives, including a Layer~1 head--MLP circuit whose ablation selectively increases loss on periodic forecasting and repetitive language passages. These results support an account of cross-modal transfer in which autoregressive pretraining creates temporal feature geometry that can be selected and specialized outside language.
Forecasting Emerges from Auto-Regressive Pretraining: Latent Predictive Structure in Language Models
Predicting how a sequence will continue is a basic problem for intelligent systems. We show that large language models contain usable foreca… (see more)sting structure before any explicit time-series supervision. A single linear readout from frozen Qwen3-0.6B hidden states maps ordinary text sequences to numerical trajectories that resemble real time series, and those trajectories can be used for straightforward forecasts. The distribution over output tokens also gives coherent, non-crossing probabilistic forecasts in a single forward pass. After time-series specialization, pretrained models show aligned gradients and improve immediately, whereas randomly initialized models spend early training in a destructive-interference regime. These findings suggest that auto-regressive pretraining already shapes representations around temporal continuation; and finetuning adapts that structure to numerical forecasting rather than creating it from scratch.
A Functional Approach to Synthesizing Routable Programmable Accelerators for Neural Networks
Paul Teng
T V Paul
Producing optimized accelerators is tedious, as even modern HDLs (Hardware Description Languages) such as Chisel, require reasoning about lo… (see more)w-level concepts. Recent functional approaches, such as Aetherling and SHIR, treat hardware as composition of pure operators. This raises the abstraction level, allowing for systematic optimizations through rewriterules for FPGAs (Field Programmable Gate Arrays).
Hidden-State Similarity Predicts Re-Elicitation After Inoculation Prompting
Fine-tuning on narrow harmful tasks can cause emergent misalignment, where models generalize harmful behavior beyond the training distributi… (see more)on. Inoculation prompting can reduce this effect by explicitly eliciting the undesired behavior during training, but recent work shows that the behavior can reappear when evaluation prompts contain cues from the training context. We study what makes such prompts effective triggers. We find that textual similarity to the inoculation prompt is an incomplete predictor: prompts are more likely to re-elicit suppressed behavior when they induce activation states similar to those produced by the inoculation context. These findings advance our understanding of how inoculation prompting modulates conditional misalignment, and suggest that activation-space analysis can help identify when suppressed behaviors remain accessible under eval-time prompts.
NeuroFaith: Evaluating Mechanistic Faithfulness of LLM Free Text Self-Explanation at the Concept Level
Jean-Noël Vittaut
Nicolas Chesneau
Marie-Jeanne Lesot
Large Language Models (LLMs) can generate plausible free text self-explanations to justify their answers. However, these natural language ex… (see more)planations may not accurately reflect the model's actual reasoning process, indicating a lack of faithfulness. Existing faithfulness evaluation methods rely primarily on behavioral tests or computational block analysis without examining the semantic content of internal neural representations. This paper proposes NeuroFaith, a flexible framework that measures the faithfulness of LLM free text self-explanation by identifying key concepts within explanations and mechanistically testing whether these concepts actually influence the model's predictions. We show the versatility of NeuroFaith across 2-hop reasoning and classification tasks. Additionally, we develop a linear faithfulness probe based on NeuroFaith to detect unfaithful self-explanations from representation space and improve faithfulness through steering. NeuroFaith provides a principled approach to evaluating and enhancing the faithfulness of LLM free text self-explanations, addressing critical needs for trustworthy AI systems.
Sirop: A Small IR for HLS with Parallel Patterns
L.T. Hildebrand
Designers of custom streaming accelerators traditionally use HDLs (Hardware Description Languages), but this is time-consuming and requires … (see more)advanced hardware expertise. C-based HLS (High-Level Synthesis) offers a higher level of abstraction and faster design time, but still requires some hardware expertise and performance is often left on the table. A promising direction is to use HLS with high-level functional parallel patterns such as map and reduce. Prior works have shown that high performance is achievable this way. However, designing such compiler systems is challenging because the optimizer must handle a large number of language primitives and interactions between them.
The Culture Funnel: You Can't Align What isn't in the Data
Ananya Sahu
Daniel D'souza
Thomas Euyang
Marzieh Fadaee
Current cultural alignment approaches focus on inference-time interventions, assuming models already contain sufficient cultural knowledge. … (see more)We argue modern LLM pipelines suffer from a cultural data funnel. Using a multidimensional tagging framework across pretraining, fine-tuning, alignment, and reasoning datasets, we show explicit cultural signals decline sharply during post-training, while geographically concentrated, task-specialized data dominates. Multilinguality enhances geographic diversity of cultural knowledge but does not ensure balanced representation. Our tags improve downstream cultural benchmark performance, demonstrating that advances require shifting focus in training data pipelines. To facilitate future research, we release our culturally tagged dataset with 5.6M samples at https://huggingface.co/datasets/CohereLabs/CultureMarkers.
The strength of flow refueling location problem formulations and an extension to cyclic routing
When Does Interleaving Prevent Emergent Misalignment?
Large language models finetuned on narrow harmful tasks are prone to emergent misalignment (EM), where harmful behavior generalizes beyond t… (see more)he training distribution. Interleaving benign data during finetuning has been proposed as a mitigation, but recent work disagrees on whether it prevents EM. In this paper, we investigate this disagreement on Qwen-2.5 7B and 32B, and find that no single property of the interleaved data, taken in isolation, accounts for the gap. Instead, much of it traces to the evaluation itself, as the standard EM benchmark is sensitive to the length of the prompts it uses, and lengthening the evaluation prompts substantially shifts measured misalignment across model sizes. We then identify a region in the model's activations that predicts whether a given interleaved set will prevent EM, and show that reformulating benign data to fall within it substantially reduces EM on both 7B and 32B. This suggests that the standard EM benchmark, which relies on short prompts, may misrepresent the effectiveness of proposed mitigations.