What is considered the most important type of error to avoid for a biometric access control system?
Correct Answer: B
When a biometric system is used for access control, the most important error
is the false accept or false acceptance rate, or Type II error, where the system would
accept an impostor.
A Type I error is known as the false reject or false rejection rate and is not as important in
the security context as a type II error rate. A type one is when a valid company employee is
rejected by the system and he cannot get access even thou it is a valid user.
The Crossover Error Rate (CER) is the point at which the false rejection rate equals the
false acceptance rate if your would create a graph of Type I and Type II errors. The lower
the CER the better the device would be.
The Combined Error Rate is a distracter and does not exist.
Source: TIPTON, Harold F. & KRAUSE, Micki, Information Security Management
Handbook, 4th edition (volume 1), 2000, CRC Press, Chapter 1, Biometric Identification
(page 10).