Conjunction Fallacy

Israeli psychologists Amos Tversky and Daniel Kahneman identified and named the conjunction fallacy in their 1982 research, formally proposing it in their 1983 publication. The famous "Linda problem" asked undergraduates to judge whether it was more probable that Linda (31, single, outspoken, bright) was a bank teller, or a bank teller active in feminism; 86% judged the conjunction more probable than the single condition, violating probability theory. Tversky and Kahneman attributed the error to the representativeness heuristic.