Leonard Jimmie Savage (born Leonard Ogashevitz; 20 November 1917 – 1 November 1971) was an American

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change. History On ...

and

statistician A statistician is a person who works with theoretical or applied statistics. The profession exists in both the private and public sectors. It is common to combine statistical knowledge with expertise in other subjects, and statisticians may wor ...

. Economist

Milton Friedman Milton Friedman (; July 31, 1912 – November 16, 2006) was an American economist and statistician who received the 1976 Nobel Memorial Prize in Economic Sciences for his research on consumption analysis, monetary history and theory and the ...

said Savage was "one of the few people I have met whom I would unhesitatingly call a genius."

Education and career

Savage was born and grew up in Detroit. He studied at

Wayne State University Wayne State University (WSU) is a public research university in Detroit, Michigan. It is Michigan's third-largest university. Founded in 1868, Wayne State consists of 13 schools and colleges offering approximately 350 programs to nearly 25,000 ...

in Detroit before transferring to

University of Michigan , mottoeng = "Arts, Knowledge, Truth" , former_names = Catholepistemiad, or University of Michigania (1817–1821) , budget = $10.3 billion (2021) , endowment = $17 billion (2021)As o ...

, where he first majored in chemical engineering, then switched to mathematics, graduating in 1938 with a Bachelor's degree. He continued at the

with a PhD on

differential geometry Differential geometry is a mathematical discipline that studies the geometry of smooth shapes and smooth spaces, otherwise known as smooth manifolds. It uses the techniques of differential calculus, integral calculus, linear algebra and multili ...

in 1941 under the supervision of

Sumner Byron Myers Sumner Byron Myers (February 19, 1910 – October 8, 1955) was an American mathematician specializing in topology and differential geometry. He studied at Harvard University under H. C. Marston Morse, Tucker, A: Interview with Albert Tucker'', Pr ...

. Savage subsequently worked at the

Institute for Advanced Study The Institute for Advanced Study (IAS), located in Princeton, New Jersey, in the United States, is an independent center for theoretical research and intellectual inquiry. It has served as the academic home of internationally preeminent scholar ...

Princeton, New Jersey Princeton is a municipality with a borough form of government in Mercer County, in the U.S. state of New Jersey. It was established on January 1, 2013, through the consolidation of the Borough of Princeton and Princeton Township, both of whi ...

, the

University of Chicago The University of Chicago (UChicago, Chicago, U of C, or UChi) is a private research university in Chicago, Illinois. Its main campus is located in Chicago's Hyde Park neighborhood. The University of Chicago is consistently ranked among the b ...

, the University of Michigan,

Yale University Yale University is a private research university in New Haven, Connecticut. Established in 1701 as the Collegiate School, it is the third-oldest institution of higher education in the United States and among the most prestigious in the wo ...

, and the Statistical Research Group at

Columbia University Columbia University (also known as Columbia, and officially as Columbia University in the City of New York) is a private research university in New York City. Established in 1754 as King's College on the grounds of Trinity Church in Manhatt ...

. Though his thesis advisor was Sumner Myers, he also credited Milton Friedman and

W. Allen Wallis Wilson Allen Wallis (November 5, 1912 – October 12, 1998) was an American economist and statistician who served as president of the University of Rochester. He is best known for the Kruskal–Wallis one-way analysis of variance, which is named ...

as statistical mentors. During World War II, Savage served as chief "statistical" assistant to

John von Neumann John von Neumann (; hu, Neumann János Lajos, ; December 28, 1903 – February 8, 1957) was a Hungarian-American mathematician, physicist, computer scientist, engineer and polymath. He was regarded as having perhaps the widest cove ...

, the mathematician credited with describing the principles upon which electronic computers should be based. Later he was one of the participants in the '' Macy conferences'' on

cybernetics Cybernetics is a wide-ranging field concerned with circular causality, such as feedback, in regulatory and purposive systems. Cybernetics is named after an example of circular causal feedback, that of steering a ship, where the helmsperson m ...

Research and contributions

His most noted work was the 1954 boo
''The Foundations of Statistics''
in which he put forward a theory of subjective and personal probability and statistics which forms one of the strands underlying

Bayesian statistics Bayesian statistics is a theory in the field of statistics based on the Bayesian interpretation of probability where probability expresses a ''degree of belief'' in an event. The degree of belief may be based on prior knowledge about the event, ...

and has applications to

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 ...

. One of Savage's indirect contributions was his discovery of the work of

Louis Bachelier Louis Jean-Baptiste Alphonse Bachelier (; 11 March 1870 – 28 April 1946) was a French mathematician at the turn of the 20th century. He is credited with being the first person to model the stochastic process now called Brownian motion, as part ...

on stochastic models for asset prices and the mathematical theory of option pricing. Savage brought the work of Bachelier to the attention of

Paul Samuelson Paul Anthony Samuelson (May 15, 1915 – December 13, 2009) was an American economist who was the first American to win the Nobel Memorial Prize in Economic Sciences. When awarding the prize in 1970, the Swedish Royal Academies stated that he "h ...

. It was from Samuelson's subsequent writing that "

random walk In mathematics, a random walk is a random process that describes a path that consists of a succession of random steps on some mathematical space. An elementary example of a random walk is the random walk on the integer number line \mathbb Z ...

" (and subsequently

Brownian motion Brownian motion, or pedesis (from grc, πήδησις "leaping"), is the random motion of particles suspended in a medium (a liquid or a gas). This pattern of motion typically consists of random fluctuations in a particle's position insi ...

) became fundamental to

mathematical finance Mathematical finance, also known as quantitative finance and financial mathematics, is a field of applied mathematics, concerned with mathematical modeling of financial markets. In general, there exist two separate branches of finance that require ...

. In 1951 he introduced the

minimax regret In decision theory, on making decisions under uncertainty—should information about the best course of action arrive ''after'' taking a fixed decision—the human emotional response of regret is often experienced, and can be measured as the value ...

criterion used in

decision theory Decision theory (or the theory of choice; not to be confused with choice theory) is a branch of applied probability theory concerned with the theory of making decisions based on assigning probabilities to various factors and assigning numerical ...

. The

Hewitt–Savage zero–one law The Hewitt–Savage zero–one law is a theorem in probability theory, similar to Kolmogorov's zero–one law and the Borel–Cantelli lemma, that specifies that a certain type of event will either almost surely happen or almost surely not happen. I ...

and Friedman–Savage utility function are (in part) named after him, as is the Savage Award given annually by the

International Society for Bayesian Analysis The International Society for Bayesian Analysis (ISBA) is a society with the goal of promoting Bayesian analysis for solving problems in the sciences and government. It was formally incorporated as a not for profit corporation by economist Arnold ...

for the best dissertations in Bayesian analysis.

Notes

External links

* Leonard Jimmie Savage papers (MS 695). Manuscripts and Archives, Yale University Library

* * {{DEFAULTSORT:Savage, Leonard Jimmie 1917 births 1971 deaths 20th-century American mathematicians American statisticians Bayesian statisticians University of Michigan alumni Princeton University faculty University of Chicago faculty Columbia University faculty University of Michigan faculty Presidents of the Institute of Mathematical Statistics Bayesian econometricians 20th-century American economists Mathematical statisticians

Education and career

Research and contributions

See also

Notes

External links