Do you know if there is any measure which quantifies how much two different plane figures overlap?
if $A_1$, $A_2$ denote the areas of figure $1$ and $2$ respectively, and their overlap area is $A_{\text{over}}$, then the measure $d$ can be define as $d = \dfrac{A_{\text{over}}}{A_1 + A_2}$? Is there any mathematical definition?