Formula
SIR model, K = i × c
Why it matters
A value below 1 means referral growth fades, and a value of 1 or more means each wave is at least as large as the last.
Glossary // K / Epidemiology
What is K-factor?
Definition
The K-factor is the number of new users each existing user brings in, calculated as invites sent per user times the conversion rate of those invites.