- Person
- Daniel Kahneman
- Lived
- 1934–2024
- Field
- Psychology, behavioural economics
- From
- Israeli-American
The story
In the mid-1950s Daniel Kahneman, a young psychology graduate of the Hebrew University, was serving in the psychology branch of the Israel Defense Forces. The state and its institutions were only seven years old, improvisation was normal, and with his bachelor's degree he was, as he later put it, the best-trained professional psychologist in the military. He was given a major assignment: to develop a method for interviewing every recruit to combat units, to screen out the unfit and help assign soldiers to suitable duties.
The existing interviews were carried out by a small group of young women, recent high school graduates chosen for their test scores and interest in psychology. They formed a general impression of each recruit and then gave global ratings, and those ratings predicted almost nothing. The year was 1955, just after the psychologist Paul Meehl had shown that simple statistical rules usually beat clinical judgment. Influenced by his book, Kahneman replaced free-form conversation with structured questions about aspects of civilian life, used to rate six specific traits, including what he remembered as masculine pride and a sense of obligation.
The interviewers nearly mutinied, feeling reduced to unthinking robots. So Kahneman compromised: after completing the six ratings as instructed, they could add their own global evaluation of the recruit however they pleased.
A few months later the first validity data came in. Kahneman recalled that the correlation between the new ratings and recruits' later performance was close to .30, compared with about .10 for the previous method, roughly tripling its predictive power. The most instructive finding was that the interviewers' final global judgment, made after the structured questions, was the best predictor of all. Trying to be reliable, he wrote, had made them valid. The system remained in use, with little modification, for many decades.
The lessons stayed with him. The puzzles he struggled with as a 21-year-old lieutenant became the seed of his later work with Amos Tversky on intuitive prediction. He returned to his army experiences in Thinking, Fast and Slow, and its central lesson, that structured judgment can beat unaided gut feeling, applies well beyond the army.
Why it matters
Kahneman's interview helped the Israeli army place soldiers more fairly and effectively, and it became an early demonstration that structured judgment beats gut feeling.
About Daniel Kahneman
Child survivor of Nazi-occupied France who, with Amos Tversky, mapped the systematic errors of human judgment, founded behavioural economics and won the 2002 Nobel Prize in economics.
More about Daniel Kahneman
- Daniel Kahneman showed how framing flips our choicesKahneman and Tversky showed that two logically identical descriptions of a choice, such as lives saved versus lives lost, can lead people to opposite decisions.
- Daniel Kahneman named the illusion of validityWatching army officer candidates, Daniel Kahneman noticed that assessors stayed confident despite proof their predictions failed. He called it the illusion of validity, his first cognitive illusion.
- Daniel Kahneman found how we remember painDaniel Kahneman showed that memories of painful experiences depend mostly on their worst moment and their end, the peak-end rule, a finding that can make medical procedures easier to bear.
- Prospect theory became the most cited paper in economicsDaniel Kahneman and Amos Tversky's 1979 paper on prospect theory, showing how people really weigh gains and losses, became the most cited paper in economics.
- Daniel Kahneman showed the eye's pupil tracks mental effortWith Jackson Beatty, Daniel Kahneman discovered that people's pupils dilate steadily as they hold more digits in memory, giving scientists a window onto mental effort.
- Daniel Kahneman's eureka moment about praise and blameWhen an Israeli flight instructor insisted that shouting worked better than praise, Daniel Kahneman realised he was seeing regression to the mean, the most satisfying eureka of his career.
- Thinking, Fast and Slow brought Kahneman's ideas to millionsDaniel Kahneman's 2011 book Thinking, Fast and Slow, describing fast intuitive and slow deliberate thinking, became an international bestseller and won major book awards.
- Kahneman and Tversky mapped the mind's shortcutsIn 1974 Daniel Kahneman and Amos Tversky published Judgment under Uncertainty: Heuristics and Biases, showing how mental shortcuts lead to predictable errors.
- Kahneman's theory helped launch behavioural economicsWhen a 1975 draft of prospect theory reached the young economist Richard Thaler, it explained his puzzles, such as the endowment effect, and helped launch behavioural economics.
- Daniel Kahneman championed adversarial collaborationDaniel Kahneman urged scientists who disagree to run joint experiments instead of trading hostile rebuttals, a practice he called adversarial collaboration.
Sources
- Daniel Kahneman: Biographical NobelPrize.org
- Daniel Kahneman Wikipedia
Another act of tikkun olam. This is part of tikkun olam, the Jewish idea of repairing the world, and every one of us can add to it.