Network structure and efficiency of observational social learning

Pooya Molavi*, Ali Jadbabaie

*Corresponding author for this work

Research output: Contribution to journalConference articlepeer-review

4 Scopus citations


This paper explores the relationship between the structure of a network of agents and how efficiently they can learn a common unknown parameter. Agents repeatedly make private observations which are possibly informative about the unknown parameter; they also communicate their beliefs over the set of conceivable parameter values to their neighbors. It has been shown that for agents to learn the realized state, it is sufficient that they incorporate in their beliefs their private observations in a Bayesian way and the beliefs of their neighbors using a fixed linear rule. In this paper we establish upper and lower bounds on the rate by which agents performing such an update learn the realized state and show that the bounds can be tight. These bounds enable us to compare efficiency of different networks in aggregating dispersed information. Our analysis yields an important insight: for agents in large balanced networks learning is much slower compared to that of a central observer regardless of the distribution of information in the network, whereas unbalanced networks result in near efficient learning if the observations of the centrally positioned agents are much more informative than others' observations.

Original languageEnglish (US)
Article number6426454
Pages (from-to)44-49
Number of pages6
JournalProceedings of the IEEE Conference on Decision and Control
StatePublished - 2012
Event51st IEEE Conference on Decision and Control, CDC 2012 - Maui, HI, United States
Duration: Dec 10 2012Dec 13 2012

ASJC Scopus subject areas

  • Control and Systems Engineering
  • Modeling and Simulation
  • Control and Optimization


Dive into the research topics of 'Network structure and efficiency of observational social learning'. Together they form a unique fingerprint.

Cite this