Definition. Repeated verifier audit [ftip-007K]
Definition. Repeated verifier audit [ftip-007K]
A repeated verifier audit of size \(N\geq 1\) records pairs \((S_i,A_i)\in \{0,1\}^2\) for candidates \(1\leq i\leq N\). Here \(S_i\) is an independently defined success label and \(A_i\) is the verifier decision, as in Definition [ftip-005Z]. Define
\[ C_i^{\rm fa}=\{S_i=0,\ A_i=1\}, \qquad \mathcal E_N^{\rm fa}=\bigcup _{i=1}^N C_i^{\rm fa}. \]The event \(\mathcal E_N^{\rm fa}\) says that at least one invalid candidate was accepted. It does not say which candidate a downstream selector returns. Write \(\phi _i=\Pr (C_i^{\rm fa})\). When \(\iota _i=\Pr (S_i=0)>0\), the conditional false-accept rate \(\eta _{+,i}=\Pr (A_i=1\mid S_i=0)\) is defined and \(\phi _i=\iota _i\eta _{+,i}\).