Leo Breiman: An important intellectual and personal force in statistics, my life and that of many others

TL;DR

This paper reflects on Leo Breiman's influential career in statistics, highlighting his transition from probability theory to applied statistics, and emphasizing his unique blend of intuition and rigor in his work.

Contribution

It provides a personal and professional overview of Leo Breiman's impact on statistics, emphasizing his innovative approach and contributions to both theoretical and applied aspects.

Findings

Breiman's work unified intuition and rigor in statistics.

His textbooks are considered classics in the field.

He significantly influenced applied statistical practices.

Abstract

I first met Leo Breiman in 1979 at the beginning of his third career, Professor of Statistics at Berkeley. He obtained his PhD with Lo\'eve at Berkeley in 1957. His first career was as a probabilist in the Mathematics Department at UCLA. After distinguished research, including the Shannon--Breiman--MacMillan Theorem and getting tenure, he decided that his real interest was in applied statistics, so he resigned his position at UCLA and set up as a consultant. Before doing so he produced two classic texts, Probability, now reprinted as a SIAM Classic in Applied Mathematics, and Statistics. Both books reflected his strong opinion that intuition and rigor must be combined. He expressed this in his probability book which he viewed as a combination of his learning the right hand of probability, rigor, from Lo\'eve, and the left-hand, intuition, from David Blackwell.