Module 2 · Scoring that you can trust · Lesson 6
Statistics, trials and CI gates
Separate signal from noise in agent evals with repeated trials, pass@k and pass^k, confidence intervals and paired comparisons, then gate merges in CI and keep watching in production.
By the end of this lesson you can
- Explain where variance in agent eval scores comes from, and run repeated trials with eve's --repeat and Claude Code headless
- Compute pass@k and pass^k from trial counts, including the unbiased estimators, and choose the right one for a given agent
- Put a confidence interval on a pass rate, cluster it by task when tasks have several trials, and estimate how many tasks you need
- Compare two agent versions with a paired analysis and say whether the difference is real
- Design a two-tier CI gate and a production monitoring loop with traces and a human review queue