What defines the crossover error rate for evaluating biometric systems?

The crossover error rate refers to the specific point at which the false acceptance rate (FAR) and the false rejection rate (FRR) are equal in a biometric system. This point is critical because it allows for an assessment of the overall effectiveness of a biometric authentication process. When evaluating biometrics, it is essential to understand how often the system mistakenly grants access to unauthorized users (false positives) versus how often it incorrectly denies access to authorized users (false negatives).

By identifying the point where these two rates are equal, organizations can gauge the reliability of the biometric system under consideration. A lower crossover error rate indicates a more reliable and effective biometric system, as it suggests that the balance between false positives and false negatives is optimal for the application. In contrast, extreme disparities between these rates can lead to a poor user experience and security vulnerabilities.