Signal vs. Noise Diagnostic

Assesses whether an observed pattern, lift, or trend is a statistically meaningful signal or an artifact of noise, small samples, or bias — running power and sample-size checks, effect-size and confidence-interval interpretation, multiple-comparison and peeking corrections, bias-source triage, and a plain-language verdict with next steps. Use when someone reports a result, metric movement, A/B lift, correlation, or dashboard anomaly and needs to know whether it's real before acting on it.