Division 1.3.1 Measurement of the FPIR (False Positive Identification Rate)

The following figure shows that the templates for the biometric sample of both fingerprints and facial image are contained in the Biometric Matching System for a number ‘n’ of identities.

The measurement process shall be as follows:

1. 1..

   A person subject to registration in the EES submits a sample of one or both of the two biometric modalities (fingerprints and facial image).

2. 2..

   The biometric verification is conducted with the biometric reference data corresponding with the identity of the person (step 1 of the figure called ‘default verification’).

3. 3..

   For a continuous sample set, the second biometric modality is obtained from the same person (either was submitted together with step 1 or it can be extracted from the biometric reference data corresponding to the identity of the person). The combined biometrics are used to run an identification on the complete gallery size excluding the biometrics of the person to whom the biometric sample belongs (step 2 of the figure called ‘identification known to be negative’). This identification process is expected to yield a zero result as the matching biometric sample has been voluntarily removed from the comparison.

   In the event the modality used in step 2 corresponds to the fingerprint, an identification (to evaluate the fingerprint identification accuracy) is carried out under the same conditions mentioned in the first subparagraph.

4. 4..

   In the case where the biometric identification returns a biometric sample (indicated as ‘match above threshold’) this is a known false positive identification (another person than the expected one is returned).

Steps 1 and 2 belong to the identity verification process that is part of the EES. Steps 3 and 4 do not belong to the identity verification process and are done for measuring the biometric accuracy performance.

The FPIR (False Positive Identification Rate) is computed as: