Base rate fallacy

Base rate fallacy, also called base rate neglect or base rate bias, is a formal fallacy. If presented with related base rate information (i.e. generic, general information) and specific information (information only pertaining to a certain case), the mind tends to ignore the former and focus on the latter.

If you overlook the base-rate information that 90% and then 10% of a population consist of lawyers and engineers, respectively, you would form the base-rate fallacy that someone who enjoys physics in school would probably be categorized as an engineer rather than a lawyer.