Maarten Sap

I am an assistant professor at CMU's LTI department with a courtesy appointment in HCII, and a part-time senior research scientist and technical AI safety lead at the Allen Institute for AI (AI2). My research focuses on (1) measuring and improving AI systems' social and interactional intelligence, (2) assessing and combatting social inequality, safety risks, and socio-cultural biases in human- or AI-generated language, and (3) building narrative language technologies for prosocial outcomes. I was named a 2025 Packard Fellow and a recipient of the 2025 Okawa Research Award.

I received my PhD from the University of Washington where I was advised by Noah Smith and Yejin Choi.
[bio for talks]

Recent updates:

November 2026 πŸ§‘β€πŸŽ“: I am taking students this year, in the areas of (a) social intelligence/user modeling in AI or (b) algorithmic and/or human-centered AI safety. Please mention my name in your application if you are interested in working with me! As mentioned on my contact page, please refrain from emailing me about your application.

October 2026 πŸ…πŸ“ƒ: I'm SUPER excited to receive Best Resource Paper Award at EMNLP 2026 for XYBench: Can LLMs Respond Pragmatically to Queries with Misconceptions? led by my PhD student Akhila Yerukola!10/2026,πŸŒ‰πŸ›οΈ,Attended COLM where my group was presenting 10 papers! See my publications or this tweet thread!

October 2026 πŸ‡­πŸ‡Ί**🏰** : Attended EMNLP where my group was presenting 8 papers! See my publications or these tweet and Bluesky threads!

August 2026 πŸŽ“πŸ“œ: Super proud of the first CMU Sapling and one of my first solo advisees, Xuhui Zhou, for successfully defending his PhD thesis! Huge congrats Xuhui!

August 2026 πŸ†πŸ“ƒ: Very honored that our paper "I Just Don't Want My Work Being Fed Into The AI Blender'': Queer Artists on Refusing and Resisting Generative AI got an Honorable Mention Award at CSCW 2026! Major congrats to the first author Jordan Taylor!!

May 2026 πŸŽ“πŸ“ƒ: The first MIT Sapling, Jocelyn Shen, successfully defended her PhD thesis! Huge congrats Jocelyn!!

December 2025 πŸ…πŸ“ƒ: Very excited to have our paper Artificial Hivemind: The Open-Ended Homogeneity of Language Models (and Beyond) selected for a Best Paper Award at NeurIPS 2025 (Datasets and Benchmarks Track)!! Huge congrats to the first author Liwei Jiang!!!

[older news]


Overarching Research Themes

Themes extracted and images generated with the OpenAI API; there may be inconsistencies.

Social Pragmatics and Theory of Mind

My research group explores how to evaluate and improve the social intelligence of AI systems, especially whether they can read context, infer intent, and respond pragmatically in multi-turn interaction. A key thread is benchmarking social reasoning and theory of mind with tasks that go beyond surface fluency, such as [SOTOPIA: Interactive Evaluation for Social Intelligence in Language Agents](https://arxiv.org/abs/2310.11667) and [FANToM: A Benchmark for Stress-testing Machine Theory of Mind in Interactions](https://arxiv.org/abs/2310.15421). More recent work like [Social Gym and SPaRTan: Benchmarking and Improving LLM Social Reasoning via Multi-Agent Game Tournaments](https://arxiv.org/abs/2608.09128) and [XYBench: Can LLMs Respond Pragmatically to Queries with Misconceptions?](https://aclanthology.org/2026.emnlp-main.2646/) pushes toward dynamic, interaction-based evaluation rather than static test sets. We are also interested in how users perceive these capabilities, as in [When Should AI Read the Room? Public Perceptions of Social Intelligence in AI Agents](https://arxiv.org/abs/2605.29938), which helps connect model performance to real-world expectations. Together, these papers suggest a shift from generic language ability toward socially grounded, situation-aware AI.

Agentic Safety and Reliance

My research group explores how to measure and reduce the risks introduced by agentic AI systems and by human over-trust in AI assistance. One major strand studies real-world agent safety and failure modes, exemplified by [OpenAgentSafety: A Comprehensive Framework for Evaluating Real-World AI Agent Safety](https://arxiv.org/abs/2507.06134) and [AI-LieDar: Examine the Trade-off Between Utility and Truthfulness in LLM Agents](https://aclanthology.org/2025.naacl-long.595/). Another line focuses on human-AI reliance and how system design shapes people’s decisions, including [Rel-A.I.: An Interaction-Centered Approach To Measuring Human-LM Reliance](https://aclanthology.org/2025.naacl-long.556/) and [Right Advice, Wrong Reasons: How Decision and Reasoning Alignment Shape Reliance on AI Advisors](https://arxiv.org/abs/2611.15732). Safety research here also looks at adversarial or vulnerable interaction contexts, such as [Lost in Delusion: Examining LLM Safety Under User Delusions and Distress](https://arxiv.org/abs/2606.00975), where the challenge is not just preventing harm but supporting safe, appropriate interaction under distress. Overall, this theme emphasizes that agentic safety is inseparable from how humans interpret, depend on, and are influenced by AI behavior.

Culturally Adaptive Responsible AI

My research group explores how to build AI systems that are culturally competent, adaptable, and fair across diverse linguistic and social contexts. A central focus is measuring whether models can recognize implicit norms and local values, as in [CCBENCH: Assessing LLM Cultural Competence via Implicitly Signaled Norms using Health Queries](https://arxiv.org/abs/2607.05405) and [NormAd: A Framework for Measuring the Cultural Adaptability of Large Language Models](https://aclanthology.org/2025.naacl-long.120/). We also study the ethical risks of missing cultural adaptation, including bias against marginalized language varieties, highlighted by [Black LLMirror: User (Self) Perceptions in Black American English Interactions with LLMs](https://dl.acm.org/doi/abs/10.1145/3772318.3791111) and [Rejected Dialects: Biases Against African American Language in Reward Models](https://arxiv.org/abs/2502.12858). More broadly, [Not Like Us, Hunty: Measuring Perceptions and Behavioral Effects of Minoritized Anthropomorphic Cues in LLMs](https://arxiv.org/abs/2505.05660) shows that cultural cues can change user experience and model behavior in subtle ways. The goal is to make personalization and localization responsible rather than merely stylistic.

Stories, Empathy, and Narrative Understanding

My research group explores how AI can support human-human connection by understanding stories, narrative intent, and the emotional structure of personal accounts. A key direction is modeling how people interpret and respond to narratives, including [HEART-felt Narratives: Tracing Empathy and Narrative Style in Personal Stories with LLMs](https://arxiv.org/abs/2405.17633) and [Modeling Empathic Similarity in Personal Narratives](https://arxiv.org/abs/2305.14246). More recent work such as [Social Story Frames: Contextual Reasoning about Narrative Intent and Reception](https://arxiv.org/abs/2512.15925) and [How Do People Challenge Racial Stereotypes Online? Counter-Story Detection Across Reddit Communities](https://arxiv.org/abs/2610.04803) extends this toward understanding how stories function in social argument, identity, and community dialogue. These papers suggest that narrative AI is not just about summarization or generation, but about recognizing why stories are told and how they shape empathy, resistance, and shared meaning. In this area, story understanding becomes a tool for better interpersonal and social communication rather than a purely text-level task.