Remembrance of Leo Breiman

Abstract

In 1994, I came to Berkeley and was fortunate to stay there three years, first as a postdoctoral researcher and then as Neyman Visiting Assistant Professor. For me, this period was a unique opportunity to see other aspects and learn many more things about statistics: the Department of Statistics at Berkeley was much bigger and hence broader than my home at ETH Z\"urich and I enjoyed very much that the science was perhaps a bit more speculative. As soon as I settled in the department, I tried to get in touch with the local faculty. Leo Breiman started a reading group on topics in machine learning and I didn't hesitate to participate together with other Ph.D. students. Leo spread a tremendous amount of enthusiasm, telling us about the vast opportunity we now had by taking advantage of computational power. Hearing his views and opinions and listening to his thoughts and ideas has been very exciting, stimulating and entertaining as well. This was my first occasion to get to know Leo. And there was, at least a bit, a vice-versa implication: now, Leo knew my name and who I am. Whenever we saw each other on the 4th floor in Evans Hall, I got a very gentle smile and "hello" from Leo. And in fact, this happened quite often: I often walked around while thinking about a problem, and it seemed to me, that Leo had a similar habit.