Formula
Geometric adstock: A(t) = x(t) + θ × A(t-1)
Why it matters
A value of 0.6 means 60 percent carries over. It sets the half-life of a campaign and guides whether to run steady spend or pulsed flights.
Glossary // C / Pharmacokinetics
What is Carryover rate (θ)?
Definition
The carryover rate, written θ, is the share of one period's advertising effect that persists into the next.