I study combinatorics, graph theory and pursuit-evasion games. I am particularly interested in the interplay between randomness and strategy. For example, I have looked at controlling random walks, guiding random graph processes, playing games on random structures, and using randomized algorithms.
Along with Stan Wagon, I won the 2015 Carl B. Allendoerfer Award, a writing award given out by the Mathematical Association of America. Our article, The Sorting Hat Goes to College, describes how we use mathematical optimization to place incoming Macalester students into first-year courses at Macalester. Stan and I are currently working with a few other colleges to optimize their placements.