Research Expertise: Algorithms and Complexity

My research spans several subfields in algorithms. In my work on massive data set algorithms, I explore what can be computed efficiently, and what is not computable. I am also interested in program checking, a paradigm for ensuring the correctness of a program by observing its behavior at run-time, and in algorithmic problems in computational biology, particularly the problem of reconstructing the evolutionary history of a set of species from phenotypic and molecular sequence observations.