Another measure is Overlap Coefficient which can be calculated as: $\frac{|A \cap B|}{min(|A|,|B|)}$.

Other measures are:

• Overlap Coefficient: $\frac{|A \cap B|}{min(|A|,|B|)}$
• Tversky index: $|A\cap B| + \alpha|A\setminus B| + \beta|B \setminus A|$ where $\alpha$ and $\beta$ are positive numbers.