PrefEngine personalization glossary
Plain-language definitions for the e-commerce personalization terms buyers ask about.
Personalization
Changing a commerce experience from consented context so it better fits the current shopper or session.
Holdout
A randomly selected group that keeps the unchanged experience so a team can measure incremental lift.
Data source
Stated directly by the shopper
Incremental lift
The improvement caused by a change after ordinary traffic mix and seasonality are separated out.
Guardrail
A hard rule that limits what an automated experience can show, change, or optimize.
Revenue per visitor
Total revenue divided by visitors. It captures conversion and order value in one useful test metric.
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