The Base Rate Fallacy is the belief that probability rates are false. The base rate fallacy is the failure to take base rates into acount when judging probability.
People tend to ignore the population base rate.
Two cab companies, the Green and the Blue, operate in the city. A witness identified the cab as a Blue cab. The court tested his ability to identify cabs under the appropriate visibility conditions. So far, this is a correct description. This is not a base rate problem.