The Multiple Comparisons in Experimentation (FWER vs FDR-BH Corrections) framework formalizes decision protocols when evaluating multi-arm variants (A/B/n testing), multi-metric dashboards, or multidimensional subgroup drilldowns; 2 governing statistical philosophies: 1) Family-Wise Error Rate (FWER): strictly controlling the probability of committing even a single Type-I error across all
K tests (
P(V≥1)≤α), implemented via conservative Bonferroni (
α′=α/K) or step-down Holm-Bonferroni (
αi=α/(K−i+1)), mandatory for mission-critical core revenue decisions; 2) False Discovery Rate (FDR): controlling the expected proportion of false discoveries among all rejected nulls (
E[V/R]≤q), implemented via the Benjamini-Hochberg (BH) step-up ranking procedure (
p(i)≤Kiq), dramatically boosting statistical power for exploratory multi-metric dashboards.