The Search for Randomness

What does it mean to say this or that is random?

In this Presidential Lecture, Persi Diaconis will explore some of our most primitive images of random phenomena: tossing a coin, shuffling cards and spinning a roulette wheel. While sometimes these tasks can yield nearly random results, we are usually lazy, and things turn out far from random — a fact savvy casino-goers can exploit. The mathematics at play applies quite broadly to the widespread misuse of probability in statistical models. The healthy Bayesian interpretation of probability makes sense of questions that crop up in our daily lives, such as deciding whether to send a child to school today or how to evaluate a medical treatment.

Diaconis is the Mary V. Sunseri Professor of Statistics and a professor of mathematics at Stanford University. His work is largely in probability, combinatorics and group theory, with a focus on applications to statistics and scientific computing. One of his research specialties concerns the convergence rates of Markov chains. He is currently interested in adapting many mathematical developments to say something useful to practitioners in large real-world simulations.