About Me
Hi! I’m Zoey. I work at Amazon SFAI developing the language model behind the Rufus assistant. I graduated as a Computer Science PhD from UIUC in 2024 advised by Prof. Jiawei Han. I’m very fortunate to be part of two generous families: the Data Mining Group and the BLENDER lab.
These days I work on RL post-training for language models, from the algorithms to the training infrastructure behind them. In 2024–2025 I focused on data selection and scaling laws for pretraining. During my PhD I built semi-supervised and weakly supervised methods for information extraction (pre-GPT), then moved to knowledge editing and hallucination mitigation.
Recent Writing
Latest
Optimizing Pass@k as Reweighting Prompts
Pass@k upweights hard problems. Training on pass@k applies that weight directly, which raises two questions: what the weight should be, and where in the training loop to apply it.
Series
Off-policy corrections
Where the policy that samples rollouts and the policy being trained come apart in LLM RL, and when a correction is worth it.