Simon Willison’s Weblog

Effective A/B Testing. Impressively comprehensive presentation on A/B testing, from theory to practice to statistical analysis of the results.

Posted 13th September 2009 at 11:49 pm

Recent articles

Embracing the parallel coding agent lifestyle - 5th October 2025
Designing agentic loops - 30th September 2025
Claude Sonnet 4.5 is probably the "best coding model in the world" (at least for now) - 29th September 2025

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