Past exam of the mathematics course of the University of Cambridge / 2022 / iii / Paper 221 / 4 / ii / Solution

Let $Y(d,m)$ be the potential violence outcome if race were set to $d$ and stop status to $m$. The substantive assumption is the structural zeroEquivalently, with the natural stop status $M(d)$, $M(d)=0$ implies $Y(d)=Y(d,M(d))=0$.