Attribution Playbook glossary
Attribution model
A rule or algorithm for dividing conversion credit across marketing touchpoints - last-click, first-click, linear, data-driven, and incrementality-based approaches.
Server-side tracking
Collecting analytics and advertising events on the store's own infrastructure rather than through third-party browser scripts, then forwarding them to platforms server-to-server.
First-party cookie
A cookie set by the store's own domain. Durable first-party identifiers - especially server-set ones - survive the browser restrictions that erase third-party and script-set cookies.
Conversions API (CAPI)
An ad platform endpoint that accepts purchase and event data directly from a merchant's server, bypassing the browser pixel. The main implementation path for server-side ad measurement.
Incrementality testing
Measuring a channel's causal effect by comparing exposed and unexposed groups (geo splits, holdouts) rather than crediting touches. The most defensible - and most effortful - attribution method.
Signal loss
The growing gap between real shopper behavior and what tracking records, caused by browser privacy features, ad blockers, and identifier deprecation.