David Joung

Principal Data Scientist

UnitedHealth Group

Led migration of pre-pay overpayment scoring to Azure Databricks and Delta Lake, improving efficiency and reducing runtime costs. Built an LLM case summarization assist and standardized monitoring across production pipelines.

Azure DatabricksDelta LakeAirflowMLFlowAzure OpenAIGPT 4Great ExpectationsPower BIXGBoostModel Risk ManagementResponsible AIPHIHIPAA

Senior Data Scientist

UnitedHealth Group

Replaced rules-order audit queues with an XGBoost ranker, improving hit rate and recoveries. Repaired flag lineage and rebuilt anomaly baselines during the 2020 telehealth surge.

XGBoostHiveA B TestingAzure DatabricksETLAnomaly Detection

Data Scientist

Built a 30-day readmission model with per-client calibration on a multi-tenant platform. Replaced a legacy risk score and introduced data quality checks for client registries.

Hivescikit learnPythonData QualityProbability CalibrationHealthcare Analytics

APS Data Scientist

Rebuilt monthly roll-rate and charge-off reporting with parameterized SAS and SQL Server, reducing production time. Built a logistic regression recovery propensity scorecard and ran an A/B outreach pilot.

SASSQL ServerLogistic RegressionA B TestingPerformance TestingModel Governance

Quantitative Analyst

Rebuilt discharge outreach lists using authorization dates, reducing staleness. Built SAS readmission flagging and standard reporting for client onboarding.

SQL ServerSSRSSASReportingHealthcare Analytics

Assistant Business Analyst

H&R Block

Rebuilt weekly field operations season reporting using Excel, Access, and SQL, reducing assembly time and improving coverage reporting.

ExcelAccessSQLReporting