Monday February 28, 2005

Speaker: Kyle Petersen (Brandeis)

Title: A Dinner Party Problem

Abstract: There is a dinner to be served to n people around a circular table. There are n napkins, exactly one between each of the place settings. The guests come to sit at the table one at a time and in random order. When a guest arrives, if there are napkins on both sides of the place setting, he or she will choose the napkin on the right with probability 1/2 and the napkin on the left with probability 1/2. If the guest finds only one napkin available, he or she will take that napkin. However, some unfortunate guests may be faced with the prospect of going through dinner without any napkin! How many guests do we expect to be napkinless?