On AI Lounge since Oct 2026
Chistian Callahan
Member #1,992FounderL2Founder and Lead Data Engineer, CGC Labs
Data Science | Data Engineering | Founder, CGC Labs
How karma works. Everyone starts with 5. You get +1 each time another member upvotes one of your posts or comments (your own upvotes don't count), and lose it if they take the upvote back. Post what you're building, answer questions and help other members to earn more.
Achievements
Plugged In ×4Connected sources: GitHub, Hugging Face, LinkedIn, X, website.How: Connected 4 sources (GitHub, LinkedIn, X or a website) in Settings
Plugged In×4Featured
Shipper ×2Projects on your profile.How: Added 5 projects to their profile
Shipper×2
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Pinned projects
A/B test analyzer that returns ship/hold/iterate/kill, not a p-value. Power vs a pre-specified MDE, CIs, effect size, and SRM checks on every result. 37 tests.
ab-testingexperimentationhypothesis-testingproduct-analytics
python
Profile README
Event-log churn scoring turned into a retention-budget decision: leakage-safe time-windowed labeling, calibrated LightGBM vs a logistic baseline, ROI simulator on 2.76M RetailRocket events. Honest result: baseline wins the holdout; CV 0.88 ± 0.06.
churn-predictionlightgbmmachine-learningmlflowpydantic
Churn, LTV segmentation, and win-back ROI on the KKBox/WSDM dataset: calibrated XGBoost (ROC-AUC 0.788 on a fixed-seed 50K-user sample), K-Means LTV segments, retention-budget simulator with synthetic cold-start mode.
churn-predictioncustomer-segmentationkkboxmachine-learningmkdocs
Healthcare operations BI on NY SPARCS inpatient data: DuckDB + SQL marts + Streamlit, case-mix adjusted facility benchmarks and XmR process control
Production churn prediction with statistical rigor — Optuna-tuned models, bootstrap 95% CIs, paired t-tests, calibration analysis on IBM Telco data. Live Streamlit dashboard.
bootstrapcalibrationchurn-predictionconfidence-intervalsmachine-learning
About
Business Intelligence Analyst | Executive Dashboards for VPs & C-Suite | KPI Governance | Founder, CGC Labs
Categories
Stack
Experience
CL
Founder & Principal · CGC Labs
CH
Business Intelligence Analyst · Community Hospital- McCook
PH
Hosebuilder 2 · Parker Hannifin
RW
Jail Deputy · Red Willow Co Sheriff Dept
RW
Deputy · Red Willow Co Sheriff Dept
RW
Jail Sergeant · Red Willow Co Sheriff Dept
