collaborators

5 papers

cs.CY2026

Estimating time spent on work tasks

Stephane Hatgis-Kessell, Tomás Aguirre, Alexander Wan +1

The task-based framework in economics models occupations as bundles of tasks. It is the standard lens for understanding how technology affects work: a new technology changes the co…

cs.CY2026

Economic Evaluations of Language Models

Alexander Wan, Stephane Hatgis-Kessell, Tomás Aguirre +2

Language models perform economically valuable work, yet they are not currently assessed for how well they perform every economically valuable task. We introduce EconEvals as an ope…

cs.LG2026

When are LLMs Sufficient Policy Optimizers for Sequential RL Tasks?

Stephane Hatgis-Kessell, Emma Brunskill

We study when large language models (LLMs) can serve as effective black-box policy optimizers for reinforcement learning (RL) tasks, i.e., when can we replace classical RL algorith…

cs.LG2026

Influencing Humans to Conform to Preference Models for RLHF

Stephane Hatgis-Kessell, W. Bradley Knox, Serena Booth +1

Designing a reinforcement learning from human feedback (RLHF) algorithm to approximate a human's unobservable reward function requires assuming, implicitly or explicitly, a model o…

cs.AI2026

Repairing Reward Functions with Feedback to Mitigate Reward Hacking

Stephane Hatgis-Kessell, Logan Mondal Bhamidipaty, Emma Brunskill

Human-designed reward functions for reinforcement learning (RL) agents are frequently misaligned with the humans' true, unobservable objectives, and thus act only as proxies. Optim…