Ehud Kalai is a prominent

Israeli American , native_name_lang = , image = , caption = , population = 110,000–150,000 , popplace = New York metropolitan area, Los Angeles metropolitan area, Miami metropolitan area, and other large metropolitan are ...

game theorist Game theory is the study of mathematical models of strategic interactions among rational agents. Myerson, Roger B. (1991). ''Game Theory: Analysis of Conflict,'' Harvard University Press, p.&nbs1 Chapter-preview links, ppvii–xi It has appli ...

and

mathematical Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics ...

economist An economist is a professional and practitioner in the social sciences, social science discipline of economics. The individual may also study, develop, and apply theories and concepts from economics and write about economic policy. Within this ...

known for his contributions to the field of

game theory Game theory is the study of mathematical models of strategic interactions among rational agents. Myerson, Roger B. (1991). ''Game Theory: Analysis of Conflict,'' Harvard University Press, p.&nbs1 Chapter-preview links, ppvii–xi It has appli ...

and its interface with

economics Economics () is the social science that studies the Production (economics), production, distribution (economics), distribution, and Consumption (economics), consumption of goods and services. Economics focuses on the behaviour and intera ...

social choice Social choice theory or social choice is a theoretical framework for analysis of combining individual opinions, preferences, interests, or welfares to reach a ''collective decision'' or ''social welfare'' in some sense.Amartya Sen (2008). "Soci ...

computer science Computer science is the study of computation, automation, and information. Computer science spans theoretical disciplines (such as algorithms, theory of computation, information theory, and automation) to Applied science, practical discipli ...

and

operations research Operations research ( en-GB, operational research) (U.S. Air Force Specialty Code: Operations Analysis), often shortened to the initialism OR, is a discipline that deals with the development and application of analytical methods to improve deci ...

. He was the James J. O’Connor Distinguished Professor of Decision and Game Sciences at

Northwestern University Northwestern University is a private research university in Evanston, Illinois. Founded in 1851, Northwestern is the oldest chartered university in Illinois and is ranked among the most prestigious academic institutions in the world. Charte ...

, 1975-2017, and currently is a Professor Emeritus of Managerial Economics and Decision Sciences.

Biography

Born in

Mandatory Palestine Mandatory Palestine ( ar, فلسطين الانتدابية '; he, פָּלֶשְׂתִּינָה (א״י) ', where "E.Y." indicates ''’Eretz Yiśrā’ēl'', the Land of Israel) was a geopolitical entity established between 1920 and 1948 ...

on December 7, 1942, Kalai moved to the US in 1963. He received his AB in mathematics from the

University of California Berkeley The University of California, Berkeley (UC Berkeley, Berkeley, Cal, or California) is a public land-grant research university in Berkeley, California. Established in 1868 as the University of California, it is the state's first land-grant univ ...

(1967) and an MS (1971) and a PhD (1972) in statistics and mathematics from

Cornell University Cornell University is a private statutory land-grant research university based in Ithaca, New York. It is a member of the Ivy League. Founded in 1865 by Ezra Cornell and Andrew Dickson White, Cornell was founded with the intention to teach an ...

. After serving as an assistant professor of statistics at

Tel Aviv University Tel Aviv University (TAU) ( he, אוּנִיבֶרְסִיטַת תֵּל אָבִיב, ''Universitat Tel Aviv'') is a public research university in Tel Aviv, Israel. With over 30,000 students, it is the largest university in the country. Locate ...

(1972–75), he was hired by

to establish a research group in game theory. He is the founding director of the Kellogg Center of Game Theory and Economic Behavior and the executive director of the Nancy L. Schwartz Memorial Lecture series. Kalai is the founding Editor of ''

Games and Economic Behavior ''Games and Economic Behavior'' (''GEB'') is a journal of game theory published by Elsevier. Founded in 1989, the journal's stated objective is to communicate game-theoretic ideas across theory and applications. It is considered to be the leadi ...

'', the leading journal in game theory. With Robert J. Aumann, Kalai founded the Game Theory Society and served as its president from 2003 to 2006. He is a Fellow of the

American Academy of Arts and Sciences The American Academy of Arts and Sciences (abbreviation: AAA&S) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, and ...

, of the

Econometric Society The Econometric Society is an international society of academic economists interested in applying statistical tools to their field. It is an independent organization with no connections to societies of professional mathematicians or statisticians. ...

, was awarded an Honorary Doctorate (Doctorat Honoris Causa) by the University of Paris at Dauphine (2010), the Sherman Fairchild Distinguished Scholar position at the

California Institute of Technology The California Institute of Technology (branded as Caltech or CIT)The university itself only spells its short form as "Caltech"; the institution considers other spellings such a"Cal Tech" and "CalTech" incorrect. The institute is also occasional ...

(1993), and was appointed the

Oskar Morgenstern Oskar Morgenstern (January 24, 1902 – July 26, 1977) was an Austrian-American economist. In collaboration with mathematician John von Neumann, he founded the mathematical field of game theory as applied to the social sciences and strategic decis ...

Research Professor at

New York University New York University (NYU) is a private research university in New York City. Chartered in 1831 by the New York State Legislature, NYU was founded by a group of New Yorkers led by then-Secretary of the Treasury Albert Gallatin. In 1832, the ...

(1991).Ehud Kalai Vitae
/ref> Since 2008, the Game Theory Society has awarded the

Kalai Prize The Prize in Game Theory and Computer Science in Honour of Ehud Kalai is an award given by the Game Theory Society. The prize is awarded for outstanding articles at the interface of game theory and computer science. Following the eligibility rule ...

for outstanding papers at the interface of

and

. The prize was named after Kalai in recognition of his contributions to bridging these two fields.

Selected Contributions

In cooperative game theory, the Kalai-Smorodinsky solution reopened the study of bargaining by showing that the long unchallenged Nash solution is not unique. He later axiomatized the Egalitarian solution to bargaining problems and, with Dov Samet, formulated its extension to general (NTU) cooperative games, unifying it with the Shapley (TU) Value.
In non cooperative game theory, the Kalai and Lehrer model of rational learning showed that rational players with truth-compatible beliefs eventually learn to play

Nash equilibria In game theory, the Nash equilibrium, named after the mathematician John Nash, is the most common way to define the solution of a non-cooperative game involving two or more players. In a Nash equilibrium, each player is assumed to know the equili ...

of repeated games. In particular, in Bayesian equilibria of repeated games all relevant private information eventually becomes common knowledge. Kalai's work on large games showed that the equilibria of

Bayesian game In game theory, a Bayesian game is a game that models the outcome of player interactions using aspects of Bayesian probability. Bayesian games are notable because they allowed, for the first time in game theory, for the specification of the soluti ...

s with many players are structurally robust, thus large games escape major pitfalls in game-theoretic modeling.
Kalai is also known for seminal collaborative research on flow games and totally balanced games; strategic complexity and its implications in economics and political systems; arbitration, strategic delegation and commitments; extensions of Arrow’s

Impossibility Theorem In contract law, impossibility is an excuse for the nonperformance of duties under a contract, based on a change in circumstances (or the discovery of preexisting circumstances), the nonoccurrence of which was an underlying assumption of the c ...

in social choice; competitive service speed in queues; and on rational strategic polarization in group decision making.

Selected publications

Cooperative Game Theory
"Other Solutions to Nash's Bargaining Problems," ''Econometrica'', 1975 (with M. Smorodinsky)
"Proportional Solutions to Bargaining Situations: Interpersonal Utility Comparisons," ''Econometrica'', 1977
"Monotonic Solutions to General Cooperative Games," ''Econometrica'', 1985 (with D. Samet)
Non cooperative Game Theory
"Finite Rationality and Interpersonal Complexity in Repeated Games," ''Econometrica'', 1988 (with W. Stanford)
"Rational Learning Leads to Nash Equilibrium," ''Econometrica'', 1993 (with E. Lehrer)
“Large Robust Games,” ''Econometrica'', 2004
Probability and Learning
"Bayesian Representations of Stochastic Processes Under Learning: deFinetti Revisited," ''Econometrica'', 1999 (with M. Jackson and R. Smorodinsky)
Economics
"The Kinked Demand Curve, Facilitating Practices, and Oligopolistic Coordination," 1986 Northwestern DP (with M. Satterthwaite; published by Kluwer, 1996))
"Observable Contracts: Strategic Delegation and Cooperation," ''International Economic Review'', 1991 (with C. Fershtman and K. Judd)
"Complexity Considerations in Market Behavior," ''The RAND Journal of Economics'', 1993 (with C. Fershtman)
Social Choice
"Aggregation Procedure for Cardinal Preferences: A Formulation and Proof of Samuelson's Impossibility Conjecture," ''Econometrica'', 1977 (with D. Schmeidler)
"Characterization of Domains Admitting Non-Dictatorial Social Welfare Functions and Non-Manipulable Voting Procedures," ''Journal of Economic Theory'', 1977 (with E. Muller)
"Path Independent Choices," ''Econometrica'', 1980 (with N. Megiddo)
Operations Research / Computer Science
"Totally Balanced Games and Games of Flow," ''Mathematics of Operations Research'', 1982 (with E. Zemel)
"Optimal Service Speeds in a Competitive Environment," ''Management Science'', 1992 (with M. Kamien and M. Rubinovitch)
“Specified Large Games,” ''Lecture Notes in Computer Science'', 2005
Mathematical Psychology
"Strategic Polarization," ''Journal of Mathematical Psychology'', 2001 (with A. Kalai)

References

{{DEFAULTSORT:Kalai, Ehud 1942 births Israeli economists Israeli emigrants to the United States 21st-century American economists Game theorists University of California, Berkeley alumni Fellows of the Econometric Society Northwestern University faculty Cornell University alumni Living people Fellows of the American Academy of Arts and Sciences Economics journal editors