David Amiel Freedman (5 March 1938 – 17 October 2008) was Professor of Statistics at 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 u ...
. He was a distinguished mathematical statistician whose wide-ranging research included the analysis of
martingale inequalities,
Markov process
A Markov chain or Markov process is a stochastic model describing a sequence of possible events in which the probability of each event depends only on the state attained in the previous event. Informally, this may be thought of as, "What happe ...
es,
de Finetti's theorem
In probability theory, de Finetti's theorem states that exchangeable observations are conditionally independent relative to some latent variable. An epistemic probability distribution could then be assigned to this variable. It is named in hono ...
, consistency of
Bayes estimators,
sampling, the
bootstrap, and procedures for testing and evaluating models. He published extensively on methods for
causal inference and the behavior of standard statistical models under non-standard conditions – for example, how
regression model
In statistical modeling, regression analysis is a set of statistical processes for estimating the relationships between a dependent variable (often called the 'outcome' or 'response' variable, or a 'label' in machine learning parlance) and one ...
s behave when fitted to data from
randomized experiment
In science, randomized experiments are the experiments that allow the greatest reliability and validity of statistical estimates of treatment effects. Randomization-based inference is especially important in experimental design and in survey samp ...
s. Freedman also wrote widely on the application—and misapplication—of statistics in the social sciences, including
epidemiology
Epidemiology is the study and analysis of the distribution (who, when, and where), patterns and determinants of health and disease conditions in a defined population.
It is a cornerstone of public health, and shapes policy decisions and evide ...
,
public policy
Public policy is an institutionalized proposal or a decided set of elements like laws, regulations, guidelines, and actions to solve or address relevant and real-world problems, guided by a conception and often implemented by programs. Public p ...
, and
law
Law is a set of rules that are created and are enforceable by social or governmental institutions to regulate behavior,Robertson, ''Crimes against humanity'', 90. with its precise definition a matter of longstanding debate. It has been vario ...
.
Biography and awards
Freedman was a fellow of the
Institute of Mathematical Statistics
The Institute of Mathematical Statistics is an international professional and scholarly society devoted to the development, dissemination, and application of statistics and probability. The Institute currently has about 4,000 members in all parts o ...
and the
American Statistical Association
The American Statistical Association (ASA) is the main professional organization for statisticians and related professionals in the United States. It was founded in Boston, Massachusetts on November 27, 1839, and is the second oldest continuousl ...
and an elected 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, a ...
. He won the 2003
John J. Carty Award for the Advancement of Science
The John J. Carty Award for the Advancement of Science is awarded by the U.S. National Academy of Sciences "for noteworthy and distinguished accomplishments in any field of science within the charter of the Academy". Established by the America ...
from the
National Academy of Sciences "for his profound contributions to the theory and practice of statistics, including rigorous foundations for Bayesian inference and trenchant analysis of census adjustment."
He was a Fellow at the
Miller Institute for Basic Research in Science in 1990, an
Alfred P. Sloan Foundation Fellow in 1964–66, and a
Canada Council
The Canada Council for the Arts (french: Conseil des arts du Canada), commonly called the Canada Council, is a Crown corporations of Canada, Crown corporation established in 1957 as an arts council of the Government of Canada. It acts as the fede ...
Fellow at
Imperial College London
Imperial College London (legally Imperial College of Science, Technology and Medicine) is a public research university in London, United Kingdom. Its history began with Prince Albert, consort of Queen Victoria, who developed his vision for a cu ...
in 1960–61.
Freedman was born in
Montreal
Montreal ( ; officially Montréal, ) is the second-most populous city in Canada and most populous city in the Canadian province of Quebec. Founded in 1642 as '' Ville-Marie'', or "City of Mary", it is named after Mount Royal, the triple ...
,
Quebec
Quebec ( ; )According to the Canadian government, ''Québec'' (with the acute accent) is the official name in Canadian French and ''Quebec'' (without the accent) is the province's official name in Canadian English is one of the thirtee ...
, Canada, on 5 March 1938. He received a B.Sc. from
McGill University
McGill University (french: link=no, Université McGill) is an English-language public research university located in Montreal, Quebec
Montreal ( ; officially Montréal, ) is the second-most populous city in Canada and most populous ...
in 1958 and a M.A. and a Ph.D. from
Princeton University
Princeton University is a private research university in Princeton, New Jersey. Founded in 1746 in Elizabeth as the College of New Jersey, Princeton is the fourth-oldest institution of higher education in the United States and one of the ...
in 1959 and 1960, respectively. He joined 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 u ...
Department of Statistics in 1961 as a lecturer and was appointed to the research faculty in 1962. He remained at Berkeley his entire career. He started his professional life as a probabilist and mathematical statistician with Bayesian leanings but became one of the world's leading applied statisticians and a circumspect frequentist.
Freedman was a consulting or testifying expert on statistics in disputes involving
employment discrimination, fair loan practices,
voting rights
Suffrage, political franchise, or simply franchise, is the right to vote in representative democracy, public, political elections and referendums (although the term is sometimes used for any right to vote). In some languages, and occasionally i ...
, duplicate signatures on petitions, railroad taxation,
ecological inference
Ecology () is the study of the relationships between living organisms, including humans, and their physical environment. Ecology considers organisms at the individual, population, community, ecosystem, and biosphere level. Ecology overlaps wi ...
, flight patterns of
golf ball
A golf ball is a special ball designed to be used in the game of golf.
Under the rules of golf, a golf ball has a mass no more than , has a diameter not less than , and performs within specified velocity, distance, and symmetry limits. Like g ...
s,
price scanner errors,
bovine spongiform encephalopathy
Bovine spongiform encephalopathy (BSE), commonly known as mad cow disease, is an incurable and invariably fatal neurodegenerative disease of cattle. Symptoms include abnormal behavior, trouble walking, and weight loss. Later in the course of t ...
(mad cow disease), and sampling. He consulted for the
Bank of Canada, the
Carnegie Commission, the
City of San Francisco, the
County of Los Angeles
Los Angeles County, officially the County of Los Angeles, and sometimes abbreviated as L.A. County, is the most populous county in the United States and in the U.S. state of California, with 9,861,224 residents estimated as of 2022. It is th ...
, and the
Federal Reserve
The Federal Reserve System (often shortened to the Federal Reserve, or simply the Fed) is the central banking system of the United States of America. It was created on December 23, 1913, with the enactment of the Federal Reserve Act, after a ...
, as well as the U.S. departments of energy, treasury, justice, and commerce. Freedman and his colleague Kenneth Wachter testified to the
United States Congress
The United States Congress is the legislature of the federal government of the United States. It is bicameral, composed of a lower body, the House of Representatives, and an upper body, the Senate. It meets in the U.S. Capitol in Washing ...
and the courts against adjusting the 1980 and 1990
census
A census is the procedure of systematically acquiring, recording and calculating information about the members of a given population. This term is used mostly in connection with national population and housing censuses; other common censuses in ...
es using estimates of differential undercounts. A 1990 lawsuit that sought to compel the
United States Department of Commerce
The United States Department of Commerce is an executive department of the U.S. federal government concerned with creating the conditions for economic growth and opportunity. Among its tasks are gathering economic and demographic data for bus ...
to adjust the census was heard on appeal by the
U.S. Supreme Court
The Supreme Court of the United States (SCOTUS) is the highest court in the federal judiciary of the United States. It has ultimate appellate jurisdiction over all U.S. federal court cases, and over state court cases that involve a point o ...
, which ruled unanimously in favor of the Commerce Department and Freedman and Wachter's analysis. With David Kaye, Freedman wrote a widely used primer on statistics for lawyers and judges published by the
Federal Judicial Center, the education and research agency for the
United States federal courts
The federal judiciary of the United States is one of the three branches of the federal government of the United States organized under the United States Constitution and laws of the federal government. The U.S. federal judiciary consists primaril ...
.
In addition to his work in
forensic statistics
Forensic statistics is the application of probability models and statistical techniques to scientific evidence, such as DNA evidence, and the law. In contrast to "everyday" statistics, to not engender bias or unduly draw conclusions, forensic sta ...
, Freedman had a broad impact on the application of statistics to important medical, social, and public policy issues, such as
clinical trial
Clinical trials are prospective biomedical or behavioral research studies on human participants designed to answer specific questions about biomedical or behavioral interventions, including new treatments (such as novel vaccines, drugs, diet ...
s,
epidemiology
Epidemiology is the study and analysis of the distribution (who, when, and where), patterns and determinants of health and disease conditions in a defined population.
It is a cornerstone of public health, and shapes policy decisions and evide ...
,
economic models
In economics, a model is a theoretical construct representing economic processes by a set of variables and a set of logical and/or quantitative relationships between them. The economic model is a simplified, often mathematical, framework design ...
, and the interpretation of
scientific experiment
An experiment is a procedure carried out to support or refute a hypothesis, or determine the efficacy or likelihood of something previously untried. Experiments provide insight into cause-and-effect by demonstrating what outcome occurs when a ...
s and
observational studies
In fields such as epidemiology, social sciences, psychology and statistics, an observational study draws inferences from a sample to a population where the independent variable is not under the control of the researcher because of ethical concern ...
. In his applied work, Freedman emphasized exposing and checking the assumptions that underlie standard methods, as well as understanding how those methods behave when the assumptions are false. He characterized circumstances in which the methods continue to perform well, and those where they break down—regardless of the quality of the data. Two of his earlier results (1963 and 1965) investigate whether or not and under what circumstances a Bayesian learning approach is consistent, i.e. when does the prior converge to the true probability distribution given sufficiently many observed data. In particular the 1965 paper with the innocent title "On the asymptotic behaviour of Bayes estimates in the discrete case II" finds the rather disappointing answer that when sampling from a countably infinite population the
Bayesian procedure fails almost everywhere, i.e. one does not obtain the true distribution asymptotically. This situation is quite different from the finite case when the (discrete) random variable takes only finite many values and the Bayesian method is consistent in agreement with earlier findings of Doob (1948).
Freedman was the author or co-author of 200 articles, 20 technical reports and six books, including a highly innovative and influential introductory statistics textbook, ''Statistics'' (2007), with Robert Pisani and Roger Purves, which has gone through four editions. The late
Amos Tversky of
Stanford University observed that "This is a great book. It is the best introduction to how to think about statistical issues...." It has a "wealth of real-world examples that illuminate principles and applications....a classic." Freedman's ''Statistical Models: Theory and Practice'' (2005) is an advanced text on statistical modeling that likewise achieves a remarkable integration between extensive examples and statistical theory.
Landmark articles by Freedman include "Statistical Models and Shoe Leather" (1991), "What is the Chance of an Earthquake?" (2003), "Methods for Census 2000 and Statistical Adjustments" (2007), and "On Types of Scientific Enquiry: The Role of Qualitative Reasoning" (2008).
Bibliography
* David A. Freedman (1963), "On the asymptotic behaviour of Bayes estimates in the discrete case I". ''The Annals of Mathematical Statistics'', vol. 34, pp. 1386–1403.
* David A. Freedman (1965), "On the asymptotic behaviour of Bayes estimates in the discrete case II". ''The Annals of Mathematical Statistics'', vol. 36, pp. 454–456.
*
*
*
** "Statistical Models and Shoe Leather" (1991). ''Sociological Methodology'', vol. 21, pp. 291–313.
** "What is the Chance of an Earthquake?" (2003). With Philip B. Stark. ''Earthquake Science and Seismic Risk Reduction'', NATO Science Series IV: Earth and Environmental Sciences, vol. 32, pp. 201–13.1
(preprint)** "Methods for Census 2000 and Statistical Adjustments" (2007). With Kenneth Wachter. ''Social Science Methodology'', Sage, pp. 232–45.
** "On Types of Scientific Enquiry: The Role of Qualitative Reasoning" (2008). ''Oxford Handbook of Political Methodology'', Oxford University Press
** "Survival analysis: A Primer". ''The American Statistician'' (2008) 62: 110–119.
See also
*
Freedman–Diaconis rule
*
Freedman's paradox
In statistical analysis, Freedman's paradox, named after David Freedman, is a problem in model selection whereby predictor variables with no relationship to the dependent variable can pass tests of significance – both individually via a t-test, ...
References
* ''Reminiscences of a Statistician: The Company I Kept'' (Springer, 2008
* ''Statistics'' 4th edition, by Freedman, Pisani and Purves (Norton, 2007
* ''Statistical Models: Theory and Practice'' by Freedman (Cambridge, 2005
External links
Personal websiteUniversity of California, Berkeley, Obituary
{{DEFAULTSORT:Freedman, David A.
Fellows of the American Statistical Association
Survey methodologists
Statistics educators
American statisticians
Canadian statisticians
American social scientists
Canadian social scientists
University of California, Berkeley College of Letters and Science faculty
Princeton University alumni
McGill University alumni
Scientists from Montreal
1938 births
2008 deaths
Probability theorists
Fellows of the Institute of Mathematical Statistics
Fellows of the American Academy of Arts and Sciences
Mathematical statisticians