Topic
Diversity, Disagreement, and Information
Aggregation
Time:
14:00-15:30, September 18, 2024
Venue:
Room 623, Mingde Main Building
Speaker:
Cheng Xienan, Postdoctoral Researcher at
Guanghua School of Management, Peking University
Host:
Zhao Wei, Assistant Professor at the School
of Economics, Renmin University of China
Abstract
Two imperfectly informed experts are hired
to advise a decision maker. The experts are assumed to report their private
information truthfully. In this paper we compare the informativeness of
different joint (conditional on the true state) distributions of the experts’
private signals, keeping the conditional marginal distribution of each expert’s
private signal given and fixed. Our comparisons use Blackwell’s (Blackwell,
1951) notion of informativeness. We interpret “diversity” as an absence of
perfect correlation among experts’ signals. Such diversity manifests itself in
a positive probability that the experts disagree on which state of the world is
more likely the true state. We find that joint distributions in which experts
disagree more frequently often have an advantage over distributions in which
disagreement is observed rarely. Disagreement may thus be a manifestation of
beneficial diversity.
Introduction to the speaker
Xienan Cheng is a Thought Leadership
Post-doctoral researcher at Guanghua School of Management, Peking University.
He obtained a Ph.D. in economics from the University of Michigan. His research
area is microeconomic theory (in particular, information economics).