Biometric Performance Statistics
- Is there an advantage in combining multiple biometrics?
- Is failure to enroll a problem with biometrics?
- Is the biometric system accuracy dependent on the user?
- How reliable/accurate are biometrics?
- Do biometric matches provide a 100% guarantee?
- What are the performance metrics (FRR, FAR, TAR, TRR, FTE, etc.)?
- How is the accuracy of a biometric system measured?
- What is a threshold?
Is there an advantage in combining multiple biometrics?
There is a potential for advancement in some applications if the combination is implemented properly. Combining biometrics incorrectly would result in performance less than that of a single measure.
Is failure to enroll a problem with biometrics?
There are some instances when an individual may not be able to provide an image of sufficient quality to the biometric system. For instance, a fingerprint may not be rolled correctly or there may be dirt on the sensor. Iris technologies are tuned to accept good quality images only. Individual disabilities may exist, such as lacking a finger. The probability of most of these instances is fairly small, but each implementation should have contingency plans in place.
Is the biometric system accuracy dependent on the user?
Yes, to some degree. Some individual users may find using certain modalities more difficult than other users.
How reliable/accurate are biometrics?
Biometric technology is continually improving. The latest government evaluations are available in the Biometrics Catalog
Do biometric matches provide a 100% guarantee?
No technology can provide a 100% guarantee. The key is to determine where the system will be successful and how to implement it correctly for the application. For example, a metal detector must have correct placement and sensitivity adjustments to work effectively and appropriately; the same is true of a biometric system.
What are the performance metrics (FRR, FAR, TAR, TRR, FTE, etc.)?
Performance metrics require more discussion than this forum allows. Please refer to http://www.biometricscatalog.org/biometrics/biometrics_101.pdf for a detailed description of performance metrics.
How is the accuracy of a biometric system measured?
The accuracy of a biometric system is determined through a series of tests beginning with an assessment of matching algorithm accuracy (technology evaluation), then assessing performance in a mock environment (scenario evaluation), followed by live testing on site (operational evaluation) before full operations begin. If done properly, users will know, to a high degree of accuracy, how the system will perform.
What is a threshold?
A value, predefined by the system administrator or the device producer, which is used to establish the degree of correlation between the biometric provided and the stored template that will result in a match.
What happens if I am enrolled in a fingerprint system and I cut my finger?
Minor scrapes typically do not impact a biometric system. Severe injuries would require a re-enrollment of the healed finger or the enrollment of a different finger. Some biometric systems allow for the enrollment of a secondary sample. For instance, an individual may be able to use his or her left index finger for verification purposes in the event he or she has injured the right index finger.