Obvious Theories: Hindsight Bias
Anything seems commonplace, once explained. - Dr. Watson to Sherlock Holmes
Debriefing
In the two previous group tasks you formulated theories for various findings. Notice that people are able to construct plausible theories which-ever way the results go.
When The American Soldier study was completed, the general public complained that it was a waste of tax-payer money because the results were all obvious.
A large volume of research in psychology has shown that people are prone to think that events are much more obvious in retrospect (e.g., Slovic & Fischhoff, 1977; Baratz, 1983; Powell, 1988; Bolt & Brink, 1991). Asked to predict the outcome of an upcoming election, people will be unsure of their predictions. But after the election is over, when asked how well they would have predicted the outcome, people are very confident that they would have correctly anticipated the actual results. In hindsight, we think we “knew it all along” (Hawkins & Hastie, 1990). In general, psychological research has established that we grossly overestimate our predictive abilities (Watts, 2011).
At the University of Leicester (UK) Karl Teigen (1986) asked students to judge the truthfulness of both actual proverbs and their opposites. When given the genuine proverb “Fear is stronger than love,” most rated it as true. But the reverse form, “Love is stronger than fear,” was also rated by most students as true. Similarly, the actual proverb “He that is fallen cannot help him who is down” was rated by most students as true. But it’s opposite was also judged by most to be true — “He that is fallen can help him who is down.” Two other proverbs that were rated as likely to be true were: “Wise men make proverbs and fools repeat them” and its opposite: “Fools make proverbs and wise men repeat them.”
As the Danish philosopher-theologian Søren Kierkegaard put it, “Life is lived forwards, but understood backwards.” We over-estimate our ability to make sense of past events. It is common for people to think we “knew-it-all-along” — when, in fact, we didn’t.
As Paul Lazarsfeld (1949) noted, “Obviously, there is something wrong with the whole argument of”obviousness.”” It is essential for researchers to be aware of the ease with which one can generate plausible theories to account for any result. There is a huge difference between explaining something once you know the results, compared with formulating the theory first, before the results are known. We should be much more suspicious of post hoc theories than a priori theories.
Intuition is important in life, but our intuitions about past events are clouded by what we know today.
The ease with which researchers can explain data after they look at it is referred to as hindsight bias. Everything is obvious in retrospect.
Slogan: Hindsight is 20/20.
Hindsight bias contributes to the feeling that research doesn’t tell us anything we didn’t already know.
There is only one sure way to avoid hindsight bias — formulate your theory before you collect your data. (The best research invites failure.)
References:
Hawkins, S. A., & Hastie, R. (1990). Hindsight: biased judgements of past events after the outcomes are known. Psychological Bulletin, Vol. 107, pp. 311-327.
Paul Lazarsfeld (1949). The American Soldier: An expository review. Public Opinion Quarterly, Vol. 13, No. 3, pp. 377-404, 380.
Paul Slovic and Baruch Fischhoff (1977). On the psychology of experimental surprises. Journal of Experimental Psychology, Vol. 3, No. 4, pp. 544-551.
Daphna Baratz (1983). How Justified is the “Obvious” Reaction? PhD Dissertation, School of Eductation, Stanford University.
Karl Teigen (1986). Psychological patterns in predicting disjunction and conjunction of clinical symptoms. Acta Psychologica, Vol. 61, pp. 183-195.
Hartmut Blank, Jochen Musch & Rüdiger F. Pohl (editors) (2007). Social Cognition, Vol 25, No. 1. Special issue on the Hindsight Bias.
Duncan J. Watts (2011). Everything is Obvious: Once you Know the Answer. New York: Crown Business.