Jun 30, 2008
By: Alvaro Fernandez
Consider Linda, a 31-year-old woman, single and bright. As a student, she was deeply concerned with discrimination and social justice and also participated in anti-nuclear protests.
Which is more probable? (a) Linda is today a bank teller; (b) Linda is a bank teller and active in the feminist movement.
Quick, what’s your answer?
If you answered (b), you are wrong. At least you are in good company (that’s what I answered the first time I saw this teaser in one of my Stanford Organizational Behavior classes).
It is more probable that Linda is a bank teller, which is a whole category, that she is both a bank teller AND active in the feminist movement, which is a subset of that category.
A recent Wall Street Journal article explains the phenomenon:
“When psychologists Daniel Kahneman and the late Amos Tversky conducted an experimental survey in the early 1980s asking people to answer this simple question, they discovered, to their surprise, that most respondents picked “b,” even though this was the narrower choice and hence the less likely one. It seems that saliency in this case, Linda’s passionate political profile trumps logic.”