Who was Daniel Kahneman
Daniel Kahneman (1934–2024) was a psychologist whose research on judgement and choice contributed to behavioural economics. He received the 2002 economic sciences prize in memory of Alfred Nobel for integrating psychological findings into economic analysis, particularly decisions under uncertainty.[1]
Childhood, education and universities
He was born in Tel Aviv during his mother’s visit to relatives, although the family home was in Paris. His autobiography described his Jewish childhood in France and the insecurity brought by German occupation. He recalled an early interest in people’s complexity, without presenting this memory as the sole explanation of his vocation.[5]
He graduated in psychology and mathematics from Hebrew University in 1954 and earned his Berkeley doctorate in 1961. He joined Princeton in 1993, became emeritus in 2007 and died on 27 March 2024.[6]
Before Princeton he held professorships at Hebrew University in Jerusalem from 1970 to 1978, British Columbia from 1978 to 1986 and Berkeley from 1986 to 1994. His career brought together psychology and public affairs, the fields in which he held emeritus titles at Princeton.[2]
Attention, effort and memory
In 1966 he published a study with Jackson Beatty on pupil diameter and short-term memory. During the task, pupils dilated as material was presented and contracted during reporting; changes related to difficulty. The study investigated a physiological measure of mental processing under specific experimental conditions.[7]
Attention and Effort, published in 1973, developed a limited-capacity theory of attention. A central question concerned interference when two activities’ combined demands exceed available resources. The book examined perception, effort and simultaneous tasks, providing an experimental foundation for themes that later appeared in his accounts of deliberate thinking.[8]
Collaboration with Amos Tversky
Kahneman explicitly credited his collaboration with Amos Tversky for the work recognised by the Nobel. His 2002 lecture organised their programme around judgement heuristics, risky choice and framing effects. They studied rapidly arising intuitions and preferences, examining how these can diverge from the standards of consistency used to assess them.[3]
Their 1974 Science paper described representativeness, availability and adjustment from an anchor. These procedures simplify estimates of probability, frequency or quantity. The authors regarded them as generally useful and economical, while identifying systematic errors associated with their use. Their contribution examined patterns of judgement as well as individual successes or failures.[9]
Prospect theory and framing
In 1979 they introduced prospect theory in Econometrica. It describes choices through gains and losses relative to a reference point rather than final wealth alone. It also distinguishes probabilities from the weights they receive in a decision. The model offered a descriptive alternative for preferences that expected utility theory did not accommodate.[10]
Their 1981 framing study demonstrated preference reversals when the same problem was expressed differently. It examined real and hypothetical monetary outcomes and problems involving human lives. The finding made the presentation of alternatives a research question: expressing equivalent consequences in another way could alter the observed choice.[11]
With Jack Knetsch and Richard Thaler, he investigated the endowment effect. In experiments published in 1990, objects such as mugs were randomly allocated and then traded. Differences between willingness to accept payment and willingness to pay persisted despite learning opportunities, while trading remained below the theoretical prediction.[12]
Experience, memory and well-being
With Peter Wakker and Rakesh Sarin, he distinguished in 1997 the utility attached to an outcome in a decision from the quality of lived experience. The latter can be studied in real time or through later recollection. Their paper examined how differences between experience and retrospective evaluation matter for choice and subsequent judgement.[13]
The day reconstruction method, published in 2004 with Alan Krueger, David Schkade, Norbert Schwarz and Arthur Stone, asks people to reconstruct the previous day’s activities and experiences. Their study of 909 employed women found correspondence with experience-sampling results. It proposed a way to measure time use and well-being in a defined study population.[14]
In 1998, Schkade and Kahneman compared students in California and the American Midwest. Reported satisfaction was similar, but participants imagining people in the other region expected greater satisfaction in California. Their focusing-illusion study showed how a salient difference, such as climate, could receive excessive weight in predictions about an entire life.[15]
Income, happiness and revisiting findings
With Angus Deaton, he analysed more than 450,000 American responses in 2010. They distinguished life evaluation from emotional well-being; on their measure, the latter levelled off around an annual income of $75,000. That figure belonged to those data and measures, rather than representing a universal amount required for happiness.[16]
In 2023 he collaborated with Matthew Killingsworth and Barbara Mellers to reconcile apparently conflicting findings. Their reanalysis identified flattening in the least happy group, approximately 20%, while other groups showed different patterns. Working across previous disagreements refined the finding and demonstrated the importance of revisiting measures and analytical assumptions.[17]
Thinking, Fast and Slow and Noise
Thinking, Fast and Slow appeared in 2011.[23] It uses two systems as an explanatory metaphor: one generates quick, intuitive responses and the other supports more deliberate, effortful processes. Kahneman explores their interaction to explain judgement and choice. They are conceptual characters organising an explanation, rather than two separate anatomical regions.[18]
In Noise, published in 2021 with Olivier Sibony and Cass Sunstein, he examined unwanted variability between judgements that should be comparable. Examples include personnel selection, judicial decisions and forecasting. Variation can occur between assessors or within one person on different occasions, directing attention towards the consistency of decision processes.[19]
Edited works and research fields
With Paul Slovic and Tversky, he edited Judgment under Uncertainty in 1982. The volume brought together research on representativeness, availability, overconfidence, risk perception and corrective procedures. This editorial work helped define a field shared by many researchers, extending beyond papers authored by Kahneman and Tversky themselves.[20]
He also coedited Well-Being with Ed Diener and Norbert Schwarz in 1999.[23] Its preface proposed a combined study of what makes experiences pleasant or unpleasant. The approach encompassed pleasure and suffering, emotions and social circumstances, seeking connections between different levels of psychological analysis of well-being.[21]
Nobel Prize and recognition
He shared the 2002 economic sciences prize with Vernon Smith, recognised for experimental economics. Their programmes were related but made distinct contributions. The Academy’s announcement highlighted Kahneman’s joint research with Tversky, who had died in 1996. The research’s shared authorship is central to understanding the award.[22]
Expert judgment in emergencies: the case of fireground commanders
In their 2009 paper, Kahneman and Gary Klein examine studies by Klein and colleagues of fireground commanders: recognising signs of collapse and deciding when to request support. They explain that reliable intuition requires environmental regularities and opportunities to learn them; personal confidence is insufficient.[4]
When reviewing an emergency exercise, this framework supports asking which cues the participant detected, what information was missing and which change would have required a different decision. The reasoning can be checked against the sequence of events, separating information available at the time from knowledge gained afterwards. This allows a decision to be assessed without rewarding it solely because the outcome happened to be favourable.
