Assistant professors Allison Koenecke and Wen Sun are among 126 early-career researchers across North America who have won 2025 Sloan Research Fellowships from the Alfred P. Sloan Foundation.

Koenecke is in the Department of Information Science in the Cornell Ann S. Bowers College of Computing and Information Science; Sun is in the Department of Computer Science at Cornell Bowers CIS; this fall, he will move to Cornell Tech.

Awarded annually since 1955, the fellowships honor exceptional U.S. and Canadian scholars whose creativity, innovation and research accomplishments make them stand out as the next generation of leaders.

“The Sloan Research Fellows represent the very best of early-career science, embodying the creativity, ambition and rigor that drive discovery forward,” said Adam F. Falk, president of the Alfred P. Sloan Foundation. “These extraordinary scholars are already making significant contributions, and we are confident they will shape the future of their fields in remarkable ways.”

The fellowships – $75,000 over two years, which the researchers can use flexibly to advance their studies – are open to scholars in seven fields: chemistry, computer science, Earth system science, economics, mathematics, neuroscience and physics.

Koenecke studies algorithmic fairness and computational social science. Her projects apply computational methods, such as machine learning (ML) and causal inference, to study societal inequities in domains including public services, online platforms, and public health.

She will use the fellowship to focus on ameliorating biases arising from ML-based speech-to-text (STT) systems, which are used in tasks including recording patient medical notes, performing hiring screens and generating courtroom transcriptions. STT transcriptions must be accurate while minimizing disparities in transcription quality across different speaker demographics. Disproportionately inaccurate transcriptions could amplify inequities in the real world, such as for patients, employees or defendants using STT. Koenecke will attempt to quantify biases in STT performance for diverse speakers across different races, age groups and health statuses, and will experiment with methods to improve STT models for fairness across voice types.

Sun and his research group develop new reinforcement learning (RL) methods that enable large language models (LLMs) to understand the world more effectively and to better follow human instructions. In particular, LLMs trained using human feedback (RLHF) exhibit enhanced abilities in reasoning, problem-solving and safety.

Sun’s group is focused on developing novel and fundamental RLHF algorithms that allow LLMs to learn faster by efficiently leveraging human data and to learn better through more effective reinforcement learning optimization. Sun is developing specialized algorithms that can scale to optimize large generative models with tens of billions of parameters, while still maintaining strong guarantees such as convergence to optimal solutions. His group also aims to develop fundamental approaches for discovering latent causal representations from interactive data.

Founded in 1934, the Alfred P. Sloan Foundation is a nonprofit institution dedicated to improving the welfare of all through the advancement of scientific knowledge. A total of 166 Cornell faculty members have won Sloan Research Fellowships since the first fellowships were awarded 70 years ago.