Curriculum vitae · Updated October 2026

Jaewook (Jake) Lee

Natural Language Processing · ML Systems

Technical Skills

  • Core: LLM Post-Training, Reinforcement Learning, Supervised Fine-tuning, Preference Optimization, LLM Evaluation, Agentic RAG, Personalization, Dialogue Systems, User Simulation, Vision-Language Model
  • Systems: Multi-Turn Conversational AI, Retrieval Systems, Tool Use, Multi-Agent Systems, Large Language Models, Vision-Language Models, vLLM, RAG Accelerators, AI Accelerators
  • Evaluation & Alignment: Human Evaluation, Benchmark Design, Evaluator Design, Reward Modeling
  • Engineering: Python, PyTorch, Hugging Face, iOS, React, Go

Experience

Apple

Machine Learning Engineer Intern · Santa Clara, CA
Jun. 2026 – Aug. 2026

  • Contributed to multimodal search systems by fine-tuning VLM for Apple's Answers, Knowledge, and Information team; additional technical details limited by confidentiality.

Amazon Web Services

Applied Scientist Intern · Seattle, WA
May 2025 – Aug. 2025

Eedi

Machine Learning Research Intern · Remote, London, UK
Jun. 2023 – Aug. 2023

  • Prototyped AnSearch, an LLM-based diagnostic-generation system that combines model outputs with domain expertise to create targeted assessments for identifying student misconceptions.

Selected Research

Agentic RAG, Tool Use & Retrieval Systems

  • Developing reinforcement learning and on-policy self-distillation methods to improve spatiotemporal reasoning in VLMs for long-video question answering. (Ongoing project)
  • Built an agentic RAG policy that trains LLMs with reinforcement learning to choose retrieval granularity and coordinate keyword/semantic search tools (EMNLP 2026).
  • Evaluated latency–accuracy trade-offs in software–hardware co-designed RAG, analyzing how approximate vs. exact nearest-neighbor retrieval affects time-to-first-token and downstream answer quality (Submitted to HPCA 2027).

Post-Training, Dialogue Systems & Model Behavior

  • Developing tool-using LLM agents that simulate students by editing executable (SymPy) solution programs to reproduce each student’s reasoning errors, to predict their future mistakes (Ongoing project).
  • Built an evaluation framework for LLM-simulated users in tutoring dialogues, measuring linguistic, behavioral, and cognitive realism and showing that surface-level plausibility can mask failures in learning dynamics (ACL 2026).
  • Developed a preference-optimization method for deriving tutor-persona steering vectors from human tutor-student dialogues, enabling interpretable control of LLM dialogue behavior without explicit persona prompting (ACL 2026 BEA Workshop).
  • Developed an Expectation Maximization-based personalization framework that infers community-level and user-specific latent preferences, enabling LLM generation under cold-start conditions (EMNLP 2025).

Applied NLP, Personalization & Human-Centered Evaluation

  • Built an iOS prototype for adaptive LLM generation that personalizes learning content to individual user preferences through interactive feedback (CHI EA 2026).
  • Led research on phonological similarity algorithms for cross-lingual keyword discovery grounded in user language priors, supporting personalized mnemonic generation (EMNLP 2025).
  • Designed evaluation pipelines combining psycholinguistic metrics with human assessment to measure memorability and creative quality in LLM-generated mnemonics (EMNLP 2024).

Education

University of Massachusetts Amherst

Ph.D. in Computer Science · Sep. 2022 – Present
Amherst, MA

  • Advisor: Dr. Andrew Lan
  • Research: LLM Post-Training and Evaluation, Personalization, Human-in-the-Loop AI
  • Mentored student-led ML/NLP research projects, including collaborations with Spotify and Adobe Research
  • Passed qualifying exam with distinction (May 2025); M.S. earned Feb. 2026

Korea University

M.E. & B.E. in Electrical and Computer Engineering · Mar. 2013 – Feb. 2022
Seoul, South Korea

  • M.E. (Jan. 2019 – Feb. 2022), Advisor: Dr. Seon Wook Kim
  • Research: Compiler Optimization, Processing-in-Memory, AI Frameworks
  • Developed ONNX Runtime integration and profiling/scheduling algorithms for PIM-based DNN inference with SK Hynix
  • Built NPU compiler tooling for memory-trace extraction and scratchpad-aware LLVM code generation with Samsung
  • B.E. (Mar. 2013 – Aug. 2019), Graduated with honors; Mandatory Military Service (21 months)

Awards

  • NAEP Math Automated Scoring Challenge Grand Prize 🏆 (2023)
    • Organized by National Center for Education Statistics (NCES)
    • Challenge to develop an accurate, LLM-based scoring system for open-ended math responses
  • NeurIPS 2022 Causal Edu Competition (Task 3), 3rd Place (2022)
    • Organized by Eedi
    • Challenge to identify causal relationships in real-world educational time-series data
  • iOS Application Hackathon Grand Prize 🏆 (2018)
    • Organized by Software Technology and Enterprise, Korea University
    • Developed a vocabulary builder app designed to help users efficiently memorize new words