Mathematical Digest

Short Summaries of Articles about Mathematics
in the Popular Press

"E-mail reveals real leaders," by Philip Ball. Nature Science Update, 20 March 2003.

Research that is the subject of this article concentrates not on the content of email, but on the senders and recipients to identify collaborative networks called "communities of practice." The communities correspond to components in a communications graph once a few edges have been removed. J.R. Tyler and colleagues at Hewlett-Packard used 200,000 email messages involving 485 HP employees to construct a communications graph for the purpose of determining how the organization at HP really functions. By doing such things as deleting links between sub-graphs of highly-connected nodes, an algorithm reduces the graph to identify the communities of practice and map the de facto structure of the firm. The claim is that this process not only identifies the communities, but also determines who is at the heart of a community. Ball writes that "The approach might even help to pinpoint the heads of criminal or terrorist networks."

--- Mike Breen