SPEAKER: Kevin Compton, BRICS, Aarhus, and University of Michigan
DATE: Friday, 5 March 1999
PLACE and TIME: Room E3-209 at 13:00.
ABSTRACT:
Random structures have many applications in computer science. For example, random graphs and random permutations are useful in average case analyses of algorithms. Over the last 25 years, researchers have made a systematic investigation of the properties of random structures using tools from logic, combinatorics and probability theory. Rather than taking the traditional approach of computing probabilities of properties on a case by case basis, they have asked whether all properties expressible in a given logic have a limiting probability in a particular class of random structures. When this happens, we say that a convergence law holds. If, in addition, the limiting probability is always 0 or 1 for all properties expressible in the logic, we say that a 0-1 law holds. We survey the different directions this area of research has taken and describe applications in the study of database query optimization and approximation of NP optimization problems.