UTCS Colloquium/Data Mining-Winter Mason/Yahoo! Research: "Inferring Social Networks From Interpersonal Communication," ACES 2.302, Wednesday, January 27, 2010, 11:00 a.m.

Contact Name: 
Jenna Whitney
Date: 
Jan 27, 2010 11:00am - 12:00pm

There is a sign-up schedule for this event that can be found
at http://www.cs.utexas.edu/department/webeven

t/utcs/events/cgi/list_events.cgi

Type of Talk: UTCS Collo

quium/Data Mining

Speaker/Affiliation: Winter Mason/Yahoo! Research

Date/Time: Wednesday, January 27, 2010, 11:00 a.m.

Loc

ation:ACES 2.302

Host: Inderjit Dhillon

Talk Title: Inferri

ng Social Networks From Interpersonal Communication

Talk Abstract:<

/p>

In order to construct and study large social networks from
commu

nication data, one must infer unobserved ties (e.g. i is
connected to
j ) from observed communication events (e.g. i
emails j). Often overl

ooked, however, is the impact this tie
definition has on the corresp

onding network, and in turn the
relevance of the inferred network to

the research question of
interest. We studied the problem of network i

nference and
relevance for two email data sets of different size andorigin. In each case, we generated a family of networks
parameter

ized by a threshold condition on the frequency of
emails exchanged bet

ween pairs of individuals. After
demonstrating that different choices

of the threshold
correspond to dramatically different network structur

es, we
then defined the relevance of these networks with respect toa series of prediction tasks that depend on various network
featur

es. In general, we find: a) that prediction accuracy is
maximized ove

r a non-trivial range of thresholds; b) that for
any prediction task

, choosing the optimal value of the
threshold yields a sizable (~ 30%)
boost in accuracy over
na?ve choices; and c) that the optimal thresh

old value
appears to be (somewhat surprisingly) consistent across data

sets and prediction tasks.

Speaker Bio: 

Winter Mas

on received his B.S. in Psychology from the
University of Pittsburgh i

n 1999. After a few years working
for the Biostatistics Center at Geor

ge Washington University,
he began graduate school at Indiana Univers

ity. Winter
received his Ph.D. in Social Psychology and Cognitive Scie

nce
in 2007. His research interests include social influence in
s

ocial networks, homophily and group identity, and group
problem solv

ing and group search.