18 January 2006

From Glabwiki

TRIANGLE COMPLEX SYSTEMS SEMINAR
18 January 2006 at 5:00 p.m.
Phillips 332 on the UNC-CH campus

Hierarchical Structure in Networks: From Football to Congress

Peter Mucha, Department of Mathematics, UNC

Abstract

The study of networks has increased dramatically in recent years across a number of areas of application, including communications, sociology, and phylogenetic biology. Important questions about communities and groupings in these applications have led to a number of competing techniques for identifying structures and hierarchies. We discuss results about the networks of (1) NCAA Division I-A college football matchups and (2) committee assignments in the U.S. House of Representatives. In college football, the underlying structure of the network strongly influences the computer rankings that contribute to the Bowl Championship Series standings. In Congress, the changes of the hierarchical structure from one Congress to the next can be used to investigate major political events, such as the "Republican Revolution" of 1994 and the introduction of the Select Committee on Homeland Security following September 11th. While many structural elements in each case are seemingly robust, we include attention to variations across identification algorithms, along with some cautionary notes.

Guests are welcome. For further information, contact Greg Shaw, gshaw@email.unc.edu, Carole Crumley, crumley@email.unc.edu, or Sue Goodman, seg@email.unc.edu