Skip to content
Li Tan
Tools

Tools

Interactive calculators and visualizers from the essays — each one small, honest, and runs entirely in your browser.

Fog drifting over the San Francisco Bay at golden hour
Bay Area fog, golden hour
  1. 01 Geo Test Power Calculator How many DMAs does a geo experiment need before it can detect your lift? Tune market count, expected lift, and noise to find out. →
  2. 02 Anomaly Detection Playground Global z-score, rolling window, seasonal decomposition — same series, very different alarms. Tune the threshold and compare. →
  3. 03 Difference-in-Differences Visualizer See how a violation of parallel trends poisons the naive estimate — and how DiD recovers the truth. →
  4. 04 Causal Method Picker Answer a few questions about your situation; get a recommendation from my working causal-inference playbook. →
  5. 05 Attribution Model Simulator Build a customer journey, then watch five attribution models fight over the credit for one conversion. →

No tracking, no backend — every tool is plain client-side JavaScript. Each links back to the essay it came from.