“The Errors of Their Ways” by Rachel Giese | The Walrus | April 2012:
Anchoring is just one example of more than a hundred identified heuristics, cognitive shortcuts that could also be called common sense, or rules of thumb, beliefs based on experience and intuition. The practice of medicine uses heuristics all the time — symptoms A, B, and C usually suggest X diagnosis, or this type of person is more prone to this disease than that one — but heuristics also play a major role in biased thinking. Israeli psychologists Daniel Kahneman and Amos Tversky wrote a formative paper in 1974 on heuristics and biases in judgment and decision-making. They identified several factors, a widespread one being representativeness, illustrated by the idea that, say, librarians tend to be sober and methodical, or that boys love to play with toy guns. As the authors note, “These heuristics are highly economical and usually effective, but they lead to systematic and predictable errors.” In other words, these generalizations hold up most of the time, but some librarians are, in fact, risk-taking party animals, and some little boys prefer Barbies.