What does it mean if the Crossover Error Rate is achieved?

The achievement of the Crossover Error Rate (CER) indicates a point in a biometric system where the rate of false rejects (Type I error) equals the rate of false accepts (Type II error). This balance point is crucial for evaluating the overall accuracy and reliability of a biometric system.

When the CER is reached, it shows that the system has achieved an optimal compromise between incorrectly denying legitimate users access (false rejections) and incorrectly granting access to unauthorized users (false acceptances). In practical terms, it reflects how well the system performs in distinguishing between legitimate and illegitimate access attempts.

Understanding the implications of the CER is important for organizations that rely on biometric systems, as it helps them assess security measures versus user convenience, ensuring that the biometric controls in place provide a satisfactory level of security without unnecessarily hindering access for legitimate users.