Metrics
Holdout test
What is Holdout test?
The only way to measure UGC lift defensibly. Serve UGC to half of PDP visitors, hide it from the other half, measure the delta. Anyone reporting UGC lift without a holdout has assumed it, not measured it.
Also calledA/B holdoutcontrol arm
See it working on a live store.
Real storefronts using the thing this page defines.
