# Vyas Kumar

> Data scientist and AI engineer based in Salt Lake City, Utah. Works on causal
> inference, healthcare machine learning, data pipelines, and marketing
> analytics. Currently a Data Analyst at REDX. Open to data science and AI
> engineering roles.

## Pages

- [Home](https://vyaskumar.com): Portfolio overview
- [About](https://vyaskumar.com/about): Background, experience, education, and skills
- [Projects](https://vyaskumar.com/projects): Case studies and technical work
- [Blog](https://vyaskumar.com/blog): Writing on data systems and AI engineering
- [Contact](https://vyaskumar.com/contact): Get in touch

## Projects

- [RHC Causal Inference](https://vyaskumar.com/projects/rhc-causal-inference): Causal effect of right heart catheterization on ICU mortality using propensity score weighting, IPW, AIPW doubly robust estimation, and E-value sensitivity analysis. AIPW ATE +0.059 (95% CI +0.033 to +0.087), propensity AUC 0.786.
- [CMS Readmission Predictor](https://vyaskumar.com/projects/cms-readmission): 30-day hospital readmission prediction on CMS DE-SynPUF Medicare claims. LightGBM with monotonic constraints, DuckDB out-of-core ETL, SHAP interpretability, MLflow tracking. AUC-ROC 0.6648 across 67K admissions.
- [REDX Email Operations](https://vyaskumar.com/projects/redx-email): End-to-end email marketing infrastructure for 100K+ weekly contacts. Raised open rates from 30% to 50% and CTR from 2% to 6% via engagement-tier segmentation.
- [Executive Reporting Pipeline](https://vyaskumar.com/projects/reporting-pipeline): Automated executive reporting with AI-driven ETL and real-time analytics dashboards.
- [Lead Data Pipeline](https://vyaskumar.com/projects/lead-pipeline): Automated lead routing between customer data platform and sales platform.
- [Atreus](https://vyaskumar.com/projects/atreus): Multi-agent AI orchestration system coordinating specialized agents with semantic memory search over a vector database.

## Blog Posts

- [I Built a Multi-Agent System So I'd Stop Being the Bottleneck](https://vyaskumar.com/blog/building-atreus): Why agents earn their keep on repetitive side-effect-heavy work, and why an agent's self-report is never evidence.
- [When Email at Scale Stops Working](https://vyaskumar.com/blog/email-at-scale): Deliverability, suppression, and engagement-tier segmentation at scale, plus how Apple Mail Privacy Protection corrupts open-rate data.
- [The 3 AM Alert That Taught Me About Monitoring](https://vyaskumar.com/blog/3am-monitoring-lesson): The agent deadlocked silently for nine hours while every crash and resource check stayed green. The dead man's switch built to catch that kind of silence.