Point to remember for CISA Exam-Biometrics
(1) Three main accuracy measures used for a biometric solution are:
(i)False-Acceptance Rate (FAR) (i.e access given to unauthorised person)
(ii) False-Rejection Rate (FRR), (i.e. access rejected to authorised person)
(iii)Cross-Error Rate (CER) or Equal-Error Rate (EER) (i.e. rate at which FAR is equal to FRR)
(2)Both FAR & FRR are inversely proportionate. As a general rule when FAR decreases, FRR increases and vice versa. Similarly if FRR decreases, FAR increases and vice versa. Adjustment point where both errors are equal is known as cross-error rate or equal-error rate.
(3)In any given scenario, most important performance indicator for biometric system is false-acceptance rate (FAR).
(4)In any given scenario, most important overall quantitative performance indicator for biometric system is CER or EER.
(5)In any given scenario, ‘Retina Scan’ has the highest reliability and lowest false-acceptance rate (FAR) among the current biometric methods.