- Person
- Daniel Kahneman
- Lived
- 1934–2024
- Field
- Psychology, behavioural economics
- From
- Israeli-American
The story
After completing his doctorate at Berkeley in 1961, Daniel Kahneman returned to the Hebrew University of Jerusalem to teach psychology. He took charge of the first-year statistics course and for some years also taught research methods, and he thought hard about which intuitions students could rely on and which they needed to learn to overcome. He later saw this teaching as the foundation of his research on judgment under uncertainty.
He was also eager to put psychology to practical use in the young State of Israel. With his colleague and friend Ozer Schild he designed a training programme for officials introducing new immigrants from countries such as Yemen to modern farming, and a training course for instructors at the Israeli Air Force flight school.
Teaching those flight instructors, Kahneman explained that praise is more effective than punishment for learning skills. A seasoned instructor objected: whenever he praised a cadet for a clean manoeuvre, the next attempt was usually worse, and whenever he screamed at a cadet for a poor one, the next was usually better. So, he said, please don't claim that reinforcement works and punishment does not.
Kahneman suddenly saw the statistical truth behind the instructor's experience. An exceptionally good or bad performance is usually followed by one closer to average, whatever the instructor does. This is regression to the mean. Because people tend to reward others when they do well and punish them when they do badly, he concluded, it is part of the human condition that we are statistically punished for rewarding others and rewarded for punishing them.
He immediately arranged a demonstration in which each participant tossed two coins at a target behind his back, without any feedback. Those who did best the first time mostly did worse on the second try, and vice versa. Kahneman called it the most satisfying eureka experience of his career, though he knew that one demonstration would not undo a lifetime of misleading experience. The same insight underlies his warning that predictions should be less extreme than the evidence they are based on, a deeply counterintuitive idea that became part of his later work with Amos Tversky on the psychology of intuitive prediction.
Why it matters
Understanding regression to the mean helps teachers, managers, coaches and doctors avoid drawing false lessons from chance ups and downs.
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 built the Israeli army's recruit interviewAt 21, Daniel Kahneman designed a structured interview for all Israeli combat recruits. It roughly tripled the interviews' predictive power and stayed in use for decades.
- 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.
- 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.