Lift of an Association Rule

Properties2

Type	Concept
Note created	Feb 17, 2025

The lift metric of an association rule measures how much more often the antecedent and consequent of a rule $A\to C$ occur together than we would expect if they were statistically independent. It is computed based on the confidence and support as per:

$$\text{lift}(A\to C)=\frac{\text{confidence}(A\to C)}{\text{support}(C)}$$

It lies in the $[0,\infty ]$; if $A$ and $C$ are independent, the lift score will be exactly 1. If the lift score is 2, $C$ is twice as likely to appear when $A$ appears.