Debabrata Basu

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Debabrata Basu bigraphy, stories - Indian-American mathematician

Debabrata Basu : biography

5 July 1924 – 24 March 2001

Debabrata Basu () (5 July 1924 – 24 March 2001) was an Indian statistician who made fundamental contributions to the foundations of statistics. Basu invented simple examples that displayed some difficulties of likelihood-based statistics and frequentist statistics; Basu’s paradoxes were especially important in the development of survey sampling. In statistical theory, Basu’s theorem established the independence of a complete sufficient statistic and an ancillary statistic. Page i in

Born in Dacca, Bengal, in unpartitioned India (now in Bangladesh), Basu was associated with the Indian Statistical Institute in India, and Florida State University in the United States.Page i in "Preface" to IMS festschrift.

Publications of D. Basu

Basu’s main articles are reprinted with his comments in

Selected articles

Biography

Debabrata Basu was born in Dacca, Bengal, unpartitioned India, now Dhaka, Bangladesh. His father, N. M. Basu, was a mathematician specializing in number theory. Young Basu studied mathematics at Dacca University. He took a course in statistics as part of the under-graduate honours programme in Mathematics but his ambition was to become a pure mathematician. Page xvii in After getting his Master’s degree from Dacca University, Basu taught there from 1947 to 1948.Page i in "Preface" to IMS festschrift. (C.f., Basu’s preface to his collected writings, edited by Ghosh.)

Following the partition of India in 1947 Basu made several trips to India. In 1948, Basu moved to Calcutta, where he worked for some time as an actuary in an insurance company. In 1950, he joined the Indian Statistical Institute as a research scholar under C.R. Rao.Page i in "Preface" to IMS festschrift. (C.f., ).

In 1950, the Indian Statistical Institute was visited by Abraham Wald, who was giving a lecture tour sponsored by the International Statistical Institute. Wald greatly impressed Basu. Wald had developed a decision-theoretic foundations for statistics in which Bayesian statistics was a central part, because of Wald’s theorem characterizing admissible decision rules as Bayesian decision rules (or limits of Bayesian decision rules). Wald also showed the power of using measure-theoretic probability theory in statistics.

After submitting in 1953 his thesis to the University of Calcutta, Basu went as a Fullbright scholar to the University of California, Berkeley. There Basu had intensive discussions with Jerzy Neyman and "his brilliant younger colleagues" like Erich Leo Lehmann.Page xvii in Basu’s "A Summing Up". Basu’s theorem comes from this time. Basu thus had a good understanding of the decision-theoretic approach to statistics of Neyman, Pearson and Wald. In fact, Basu is described as having returned from Berkeley to India as a "complete Neyman Pearsonian" by J. K. Ghosh.Page viii of J. K. Ghosh’s preface to the selected essays of Basu.

Basu met Ronald A. Fisher in the winter of 1954–1955; he wrote in 1988, "With his reference set argument, Sir Ronald was trying to find a via media between the two poles of Statistics – Berkeley and Bayes.The term "Berkeley" has several meanings, here. Basu refers to the leadership of Jerzy Neyman’s department of statistics at the University of California at Berkeley in the world of frequentist statistics. Secondly, Basu alludes to the British philosopher George Berkeley who criticized the use of infinitesimals in mathematical analysis; Berkeley’s criticisms were answered by Thomas Bayes in a pamphlet. My efforts to understand this Fisher compromise led me to the Likelihood Principle".Page xvii in Ghosh (ed.). In their festschrift for Basu, the editors Malay Ghosh and Patak write that

"[Basu's] critical examination of 

both the Neyman–Pearsonian and the Fisherian modes of inference eventually forced him to a Bayesian point of view, via the likelihood route. The final conversion to Bayesianism came in January 1968, when Basu was invited to speak at a Bayesian Session in the Statistics Section of the Indian Science Congress. He confesses that, while preparing for these lectures, he became convinced that Bayesian inference did indeed provide one with a logical resolution of the underlying inconsistencies of both the Neyman–Pearson and the Fisherian theories. Since then, Dr. Basu became an ardent Bayesian and, in many of his foundation papers, pointed out the deficiencies of both the Neyman–Pearsonian and the Fisherian methods."

After 1968, Basu began writing polemical essays, which provided paradoxes to frequentist statistics, and which produced great discussion in statistical journals and at statistical meetings. Particularly stimulating papers were Basu’s papers on the foundations of survey samplingGhosh’s editorial notes. There is an extensive literature discussing Basu’s problem of estimating the weight of the elephants at a circus with an enormous bull elephant named "Jumbo"

and on the Fisher randomization test. 

After teaching at the Indian Statistical Institute Dr. Basu moved to the United States and taught statistics at Florida State University from 1975 to 1990 when he was made an emeritus professor; he has supervised six students.

About Basu