**UBC Mathematics Department**

*http://www.math.ubc.ca*

## Colloquium Abstract: Dr. Peter March, Ohio State University and UBC

Friday, January 12th at 3:35 p.m. in MATH 104

Abstract: If a mathematical or physical object can be thought of
as being built up from components of various sizes then one can
consider, for a randomly chosen object, the distribution of the
components ranked by size. This leads to probability distributions on
the set of infinite sequences *(x, y, z, ... )* such that
* x >= y >= z >= ... >= 0 * and
* x + y + z + ... = 1.*

An interesting family of such distributions, the Poisson-Dirichlet
distributions, pops up frequently in seemingly diverse parts of pure
and applied mathematics. By examining features common to several
examples, one is lead to characterizations of the Poisson-Dirichlet
family which were found recently by Pitman and by Zabell.

*Coffee, tea and cookies will be served in Math Lounge (Annex)
Room 1115, 3:15 p.m.

Return to this week's seminars