Diagnosing Experiment Results
by PostHog469d1773e9cbNo licenseListed Oct 8, 2026Updated Oct 8, 2026
Diagnoses bias, anomalies, and strange results on a PostHog experiment. Covers 0-exposure experiments, sample ratio mismatch, identity fragmentation, multi-variant exposure, uneven-split exclusion bias, significance traps (peeking, A/A, Bayesian vs Frequentist), PostHog-vs-SQL discrepancies, surprises after mid-run edits, and qualitative follow-up via a variant-split survey. TRIGGER when: user asks 'is my experiment biased?' or 'why 0 exposures?', references the bias banner, says a variant looks strange / wrong / off, sees significance flipping or A/A significance, finds PostHog numbers disagreeing with their SQL, reports surprises after mid-run edits, or wants qualitative feedback or a survey for an experiment. DO NOT TRIGGER when: creating an experiment (use creating-experiments), only configuring rollout (use configuring-experiment-rollout) or metrics (use configuring-experiment-analytics), or only asking lifecycle questions (use managing-experiment-lifecycle).
Only the file list is public. File contents are available once the skill is installed in a workspace.
| Path | Size | Type |
|---|---|---|
| references/bias-and-skew.md | 29 KB | text/markdown |
| references/diagnostic-snapshot.md | 7.9 KB | text/markdown |
| references/empty-experiment.md | 18.6 KB | text/markdown |
| references/interpretation.md | 15.4 KB | text/markdown |
| references/mid-run-changes.md | 17.1 KB | text/markdown |
| references/numbers-vs-sql.md | 17.3 KB | text/markdown |
| references/qualitative-feedback.md | 13.8 KB | text/markdown |
| SKILL.md | 15.7 KB | text/markdown |
Source and attribution
Source:PostHog/ai-plugininskills/diagnosing-experiment-resultsat commit469d177
License: No license
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