Data scientist and UCLA Anderson MSBA. Formerly Chief Strategy Officer; now focused on applied analytics and machine learning. I turn ambiguous business problems into models and decision tools.
npx lyhjeremy↑ run that in your terminal for the interactive version of this README
- Modeling · scikit-learn · PyTorch · XGBoost · regression / classification / clustering · time series · neural networks · causal inference · survival analysis · A/B testing
- Optimization · Gurobi · LP / IP / QP / non-convex programming · branch-and-bound · LP duality · gradient descent · simulation · Monte Carlo
- GenAI · LLM prompting · RAG · embeddings · vector databases · fine-tuning · OpenAI / Anthropic APIs · NLP
- Agents & orchestration · LangChain · LangGraph · agentic workflows · tool use · retrieval pipelines · multi-step reasoning
- Data & tools · Python · R · SQL · Snowflake · Airflow · Spark / PySpark · Tableau · Power BI · Excel · Git · GCS · Jupyter
- Deployment & apps · GitHub Pages · Streamlit · interactive dashboards · desktop apps · live demos · reproducible pipelines
Selected work spanning generative AI, statistical modeling, and machine learning. Each title links to the code; the Live link opens a plain-language write-up in the browser. The full set of projects is in the dropdown below.
| Project | Methods | |
|---|---|---|
| Wine Sommelier RAG | Semantic search over 130k wine reviews using hybrid BM25 and dense retrieval with a cross-encoder reranker, evaluated on retrieval quality (precision and nDCG up roughly 21%). | Live |
| Marathon Training Agent | A LangGraph agent that iteratively drafts and revises a training plan until it satisfies explicit safety checks, with a Streamlit interface. | Live |
| World-Record Half-Lives | Survival analysis (Kaplan-Meier and Cox regression) of how long track-and-field world records stand, estimating each record's probability of falling. | Live |
| Performance Continuum | Distribution fitting and extreme-value theory locating any marathon time within a field of 31,842 finishers and quantifying how far the world record sits beyond it. | Live |
| National Strength Profiles | K-means clustering and PCA of 43 nations across five athletics disciplines, identifying five distinct performance archetypes. | Live |
| Scoring-Table Fairness Audit | Non-parametric hypothesis testing (Kruskal-Wallis) on 6,400 elite marks, assessing whether World Athletics points are comparable across events. | Live |
More projects (16 additional repositories)
| Project | Methods | |
|---|---|---|
| Marathon Strategy RAG | Grounded retrieval-augmented Q&A that cites its sources, evaluated with an LLM-as-judge faithfulness metric; includes a LangChain LCEL implementation. | Live |
| Wine Pairing Agent | A LangGraph agent that infers a wine style and calls the retriever as a LangChain tool, with full run tracing. | Live |
| Project | Methods | |
|---|---|---|
| The Heat Tax | Regression of Boston Marathon field times on temperature: roughly one minute slower per °F (r = 0.86). | Live |
| The Negative-Split Myth | Split analysis showing only 2.5% of 31,912 Boston finishers ran a faster second half. | Live |
| Hitting the Wall | Per-5K split analysis locating where marathon pace decays, around 30 km. | Live |
| Boston BQ Fairness | An equity analysis of Boston qualifying standards across age and gender brackets. | Live |
| Marathon Majors Course Difficulty | A three-framework comparison of finishing speed across the six World Marathon Majors. | Live |
| Marathon Shoe Revolution | Decomposition of recent marathon progression into footwear effects versus other factors. | Live |
| Project | Methods | |
|---|---|---|
| Are Song Lyrics Getting Simpler? | Fifty years of Billboard lyrics: longer and more repetitive over time, with roughly stable vocabulary. | Live |
| Love Island Lexical Analysis | A corpus study of lexical complexity in reality-television dialogue. | Live |
| EPUB Reading-Level Analyzer | An in-browser tool reporting a book's reading level and vocabulary load from an EPUB file. | Live |
| Mandarin Learning Reader | An interactive Mandarin reader built from any Chinese EPUB, with per-character pinyin, read-aloud, and offline pronunciation grading. | Live |
| Cantonese Learner | A mobile Cantonese speaking tutor built from current Hong Kong news articles. | Live |
| Project | Methods | |
|---|---|---|
| Wine Score Inflation | How 130k professional reviews cluster into an effective 8-point band on the nominal 100-point scale. | Live |
| When Can I Retire? | A Monte-Carlo retirement simulator estimating the probability a portfolio lasts through retirement. | Live |
| Project | Methods | |
|---|---|---|
| Leave Time Optimizer | A routing tool that computes when to depart to arrive on time, using the Google Maps API. | Live |
| EPUB → Audiobook | A desktop app that converts e-books into read-along audiobooks (English and Chinese). | Live |
| Podcastify | Converts an e-book or article into a two-host podcast with synthetic voices. | Live |
- Co-founder & Chief Strategy Officer, Casual Ace Learning Centre — grew enrollment 5.2× to over 1,000 students across six centers.
- MSBA, UCLA Anderson · graduate analytics coursework, Georgia Tech · BBA (Accounting & Finance), University of Hong Kong.
14 marathons, Berlin personal best of 2:48 · WSET Level 3 in wine.