David Blackwell (Mathematician Series) –36×36”
Melted hand cast encaustic crayons
David Blackwell (1919-2010) was born in Illinois to a father who worked in the railroad business and a homemaker mother. He recalled that, as a student in an integrated school, he was unaware of discrimination against African-Americans during his childhood. At the age of 16, he entered the University of Illinois, and by the age of 22, he had earned a PhD in mathematics there.
For his postdoc, he was welcomed in 1941 by the Institute for Advanced Study at Princeton, a prestigious honor. One of the founding principles of the IAS is to award positions on the basis of merit alone, regardless of race, religion, or gender. Therefore, the staff at IAS were quite open to Blackwell, but unfortunately, Princeton itself had not yet evolved to that merit-based mindset. Therefore, when his postdoc was over, Blackwell went in search of a college that would value him as a permanent faculty member.
He landed a position at Howard University and remained there for ten years, publishing over twenty papers and chairing the mathematics department. One of his special interests was game theory, the mathematics of bluffing and dueling, which had applications in real world war situations. He published a book with M.A. Girshick called Theory of Games and Statistical Decisions, which is still popular today. Because his work was of interest to the Rand Corporation, from 1948 to 1950, he spent his summers there applying game theory to theoretical military situations.
UC Berkeley hired him as a visiting professor in 1954, and the next year, he became a full professor and then Statistics Department Chair in 1956. Evidently, he loved Berkeley since he remained there and published prolifically until his retirement in the late 1980s.
With C.R. Rao, he developed the Rao-Blackwell theorem, which has many statistical applications. One example is the counting of endangered birds to decide whether they are becoming more or less endangered. Without Rao-Blackwell’s theorem, ecologists might simply place random cameras in forests and count how many birds are caught in the footage. But using the theorem, it’s possible to get a much more accurate number of how many birds exist by positioning cameras in the densest areas of their population and not wasting camera time in areas the birds hardly ever frequent. The theorem enables scientists to make more informed and correct estimates.
In 1965, Blackwell was elected to the National Academy of Sciences. Just as important as his original contributions to the field of mathematics was his rapport with his students. According to the accounts of students and fellow professors after he passed away in 2010, he was an excellent professor who could explain complex concepts in elegant, simple terms. Although he supervised 65 doctoral students during his career, he preferred teaching undergraduate classes, and students signed up for courses merely because he was the instructor. Besides being a world-class mathematician, he is remembered fondly for his engaging and kind personality.
