David Schmeidler | |
|---|---|
| Born | 1939 (1940) Kraków, Poland |
| Died | 17 March 2022(2022-03-17) (aged 82–83) |
| Alma mater | Hebrew University of Jerusalem |
| Scientific career | |
| Fields | |
| Institutions | |
| Thesis | Games with a continuum of players (1969) |
| Doctoral advisor | Robert Aumann |
| Doctoral students | Itzhak Gilboa |
| Academic career | |
| Information atIDEAS / RePEc | |
David Schmeidler (1939 – 17 March 2022) was an Israeli mathematician and economic theorist. He was a Professor Emeritus atTel Aviv University and theOhio State University.
David Schmeidler was born in 1939 inKraków, Poland. He spent the war years inRussia and moved back to Poland at the end of the war and to Israel in 1949. From 1960 to 1969 he studiedmathematics at theHebrew University of Jerusalem (BSc, MSc, and PhD), the advanced degrees under the supervision ofRobert Aumann. He visited theCatholic University of Louvain andUniversity of California at Berkeley before joiningTel-Aviv University in 1971, holding professorships instatistics,economics, andmanagement. He held a part-time position as professor of economics at theOhio State University since 1987. Schmeidler died on 17 March 2022.
Schmeidler's early contributions were ingame theory andgeneral equilibrium theory. He suggested a new approach to solvingcooperative games – thenucleolus – based on equity as well as feasibility considerations. This concept, originating from Schmeidler's PhD dissertation, was used to resolve a 2000 years old problem. Robert Aumann andMichael Maschler, in a paper published in 1985, showed that a conundrum from theBabylonian Talmud, which defied scholars’ attempts at comprehension over two millennia, was naturally resolved when applying the concept of the nucleolus.[1]
Schmeidler also pioneered the study ofnon-atomic strategic games,[2] in which each player has negligible impact on the play of the game, as well as the related concept of “congestion games”, where a player's payoff only depends on the distribution of the other players’ strategic choices (and not on individual choices).
Schmeidler has made many other contributions, ranging from conceptual issues inimplementation theory, to mathematical results inmeasure theory. But his most influential contribution is probably indecision theory. Schmeidler was the first to propose a general-purpose, axiomatically-based decision theoretic model that deviated from the Bayesian dictum, according to which any uncertainty can and should be quantified by probabilities. He suggested and axiomatizedChoquet Expected Utility,[3][4] according to which uncertainty is modeled by acapacity (not-necessarily-additive set function) and expectation is computed by theChoquet integral.
While this approach can be used to explain commonly observed behavior inEllsberg's experiments, Schmeidler's motivation was not to explain psychological findings. Rather, along the lines attributed toFrank Knight andJohn Maynard Keynes, the argument is normative, suggesting thatit is not necessarily more rational to be Bayesian than not.[5] While in the experiments, drawing balls from urns, one may adopt a probabilistic belief, in real life one often couldn't find a natural candidate for one's beliefs.[6]
WithElisha Pazner, he introduced the notion ofegalitarian equivalence - a criterion forfair division of homogeneous resources, that has advantages over the previously studied criterion ofenvy-freeness.
With his student,Itzhak Gilboa, David Schmeidler also developed the theorymaxmin expected utility[7] andcase-based decision theory.[8][9] He has also served as the advisor ofPeter Wakker,Shiri Alon, andXiangyu Qu.
David Schmeidler was a Fellow of theEconometric Society, Honorary Foreign Member of theAmerican Academy of Arts and Sciences, and a Member of theIsraeli Academy of Sciences and Humanities. He served as the President of theGame Theory Society (2014–2016).
