Results of summer '97 research with my undergraduate student, Andromeda
Yelton. Our paper gives a classification, called the cyclic mean, of quadratic
irrationals by the closeness of their rational approximations, and explores
properties of this mean. In particular, we give several criteria for comparing
the means of two quadratic irrationals without having to compute them explicitly!
These have application in the study of random walks on the circle.