Senior Data Scientist
17 years building and validating statistical models at CDC and NIOSH. Now building detection, credit-scoring and agentic AI systems at OhMyCode LLC on AWS, Snowflake and Databricks.
Senior Data Scientist with a Doctor of Science degree and 17 years transforming complex healthcare data into actionable insights at CDC and NIOSH, now applied to detection, scoring and agentic AI at OhMyCode LLC.
Bridging technical analysis and executive decision-makingβtranslating statistical results into recommendations leadership can act on.
Detection and scoring systems, healthcare analytics, RAG systems and AI agents
RAG pipeline: PDF ingestion into ChromaDB, hybrid BM25 + dense search with Reciprocal Rank Fusion, FastAPI backend, RAGAS evaluation on a synthetic golden dataset. Deployed via Docker / Cloud Run.
Autonomous LLM agent that plans multi-step research tasks, queries web sources, synthesizes findings, and generates structured reports with citations.
Automated pipeline to transcribe, summarize, and surface insights from HK podcast episodes using speech-to-text and LLM summarization, enabling searchable audio knowledge bases.
End-to-end scoring pipeline with reject inference implemented three ways and scored against ground truth. Found and fixed four deployed defects, including a calibration bug that moved scores 45.6 points.
Python port of a CDC production R/SAS pipeline: six-source weekly merge, change-point alert kept distinct from a magnitude threshold, completeness and cross-source reconciliation checks.
Local AI coding agent with Splunk cost, latency and DLP observability; detected anomalies trigger self-healing model-router re-weighting. 6th place, Splunk Dashboard Contest 2026.
AWS-hosted MCP server exposing regime detection, Monte Carlo VaR and FOMC stress tests to Amazon Alexa+, backed by a 14-tab Streamlit dashboard.
Rule engine for ICD-10βHCC mapping and NDC drug-interaction checks, paired with a tool-calling agent that acts on rule outputs.
Multi-provider LLM layer on AWS Bedrock (Nova Pro, Converse API) and Gemini, with head-to-head scoring of latency and output quality on identical prompts.
Predictive models and NLP for CDC surveillance data
Entity extraction using Spark NLP
Propensity score models for policy analysis
CI/CD for reproducible ML workflows
2025βPresent
OhMyCode LLC
Detection and alerting pipelines, credit scoring with calibration QA, and agentic AI on AWS, Snowflake and Databricks.
2022β2025
CDC (DNI Contractor)
Lead predictive and causal models. Advanced NLP analyses.
2019β2022
CDC (Goldbelt, TJFACT)
NVDRS and COVID-19 surveillance analytics.
2008β2017
CDC, NIOSH
Cost-effectiveness modeling for prevention programs.
2014β2020
Georgia Southern University
Biostatistics and epidemiological modeling research.
"A cross-sectional study of teens' health skills that were enhanced through school health education and their associations with mental health-related outcomes" β Health Education & Behavior
Accepted Β· forthcoming 2026
"Adolescent and Parent Perspectives on Sexual and Reproductive Health Information: A Cross-Sectional Study of Perceived Usefulness and Comfort" β Journal of Adolescent Health
Accepted Β· forthcoming 2026
"Evaluation of the Reliability and Validity of the Perceptions of Skills Enhanced Through School Health Education (PSE-SHE) Measure" β Journal of School Health
doi.org/10.1111/josh.70038
"Updated assessment of occupational safety and health hazards of climate change" β Journal of Occupational and Environmental Hygiene, 20(5β6):183β206
doi.org/10.1080/15459624.2023.2205468
"Maternal exposure to air pollution and risk of Autism in children: A systematic review and meta-analyses" β Environmental Pollution
doi.org/10.1016/j.envpol.2019.113307
Send me a message or reach out via social links.
Senior Data Scientist | Healthcare | NLP | MLOps
hkchun18@gmail.com
17 years building and validating predictive, causal and detection models on large real-world data. Azure/Databricks, Snowflake, AWS, NLP, MLOps and agentic AI.
Data Scientist β OhMyCode LLC (2025βPresent)
Statistician / Data Scientist β CDC (2022β2025)
Data Analyst β CDC (2019β2022)
Economist / Health Scientist β CDC (2008β2017)
Sc.D., Work Environment Policy β UMass Lowell
M.A., Economics β Boston University
Python, PySpark, SQL, R, SAS, XGBoost, HuggingFace, Spark NLP, Azure ML, Databricks, Snowflake, AWS Bedrock, Power BI, MLflow
Azure AI-900, DP-900, AZ-900