Naïve Learning in Social Networks: Convergence, Influence and Wisdom of Crowds
We study learning and influence in a setting where agents communicate according to an arbitrary social network and naïvely update their beliefs by repeatedly taking weighted averages of their neighbors’ opinions. A focus is on conditions under which beliefs of all agents in large societies converge to the truth, despite their naïve updating. We show that this happens if and only if the influence of the most influential agent in the society is vanishing as the society grows. Using simple examples, we identify two main obstructions which can prevent this. By ruling out these obstructions, we provide general structural conditions on the social network that are sufficient for convergence to truth. In addition, we show how social influence changes when some agents redistribute their trust, and we provide a complete characterization of the social networks for which there is a convergence of beliefs. Finally, we survey some recent structural results on the speed of convergence and relate these to issues of segregation, polarization and propaganda.
|Date of creation:||Jun 2007|
|Date of revision:|
|Contact details of provider:|| Postal: Corso Magenta, 63 - 20123 Milan|
Web page: http://www.feem.it/
More information through EDIRC
Please report citation or reference errors to , or , if you are the registered author of the cited work, log in to your RePEc Author Service profile, click on "citations" and make appropriate adjustments.:
- A. Banerjee & Drew Fudenberg, 2010.
"Word-of-Mouth Communication and Social Learning,"
Levine's Working Paper Archive
425, David K. Levine.
- Bogaçhan Çelen & Shachar Kariv, 2004. "Distinguishing Informational Cascades from Herd Behavior in the Laboratory," American Economic Review, American Economic Association, vol. 94(3), pages 484-498, June.
- Ellison, Glenn & Fudenberg, Drew, 1993.
"Rules of Thumb for Social Learning,"
Journal of Political Economy,
University of Chicago Press, vol. 101(4), pages 612-43, August.
- Ellison, Glenn & Fudenberg, Drew, 1993. "Rules of Thumb for Social Learning," Scholarly Articles 3196332, Harvard University Department of Economics.
- Allison, G. & Fudenberg, D., 1992. "Rules of Thumb for Social Learning," Working papers 92-12, Massachusetts Institute of Technology (MIT), Department of Economics.
- G. Ellison & D. Fudenberg, 2010. "Rules of Thumb for Social Learning," Levine's Working Paper Archive 435, David K. Levine.
- Ellison, Glenn & Fudenberg, Drew, 1992. "Rules of Thumb for Social Learning," IDEI Working Papers 17, Institut d'Économie Industrielle (IDEI), Toulouse.
- Volij, Oscar & Palacios-Huerta, Ignacio, 2004.
"The Measurment of Intellectual Influence,"
Staff General Research Papers
10797, Iowa State University, Department of Economics.
- Vieille, Nicolas & Rosenberg, Dinah & Solan, Eilon, 2006. "Informational externalities and convergence of behavior," Les Cahiers de Recherche 856, HEC Paris.
- Ballester, Coralio & Calvó-Armengol, Antoni & Zenou, Yves, 2005.
"Who’s Who in Networks. Wanted: The Key Player,"
CEPR Discussion Papers
5329, C.E.P.R. Discussion Papers.
- Coralio Ballester & Antoni Calvo-Armengol & Yves Zenou, 2005. "Who's Who in Networks. Wanted: the Key Player," NajEcon Working Paper Reviews 666156000000000586, www.najecon.org.
- Coralio Ballester & Antoni Calvó-Armengol & Yves Zenou, 2004. "Who's Who in Networks. Wanted: The Key Player," Working Papers 178, Barcelona Graduate School of Economics.
- Galeotti, Andrea & Goyal, Sanjeev, 2007. "A Theory of Strategic Diffusion," Economics Discussion Papers 2983, University of Essex, Department of Economics.
- Gale, Douglas & Kariv, Shachar, 2003. "Bayesian learning in social networks," Games and Economic Behavior, Elsevier, vol. 45(2), pages 329-346, November.
- Abhijit V. Banerjee, 1992. "A Simple Model of Herd Behavior," The Quarterly Journal of Economics, Oxford University Press, vol. 107(3), pages 797-817.
- Sobel, Joel, 2000. "Economists' Models of Learning," Journal of Economic Theory, Elsevier, vol. 94(2), pages 241-261, October.
- Nicolas Vieille & E. Solan & D. Rosenberg, 2006. "Informational Externalities and Convergence of Behavior," Post-Print halshs-00120992, HAL.
- Syngjoo Choi & Douglas Gale & Shachar Kariv, 2005. "Learning in Networks: An Experimental Study," Levine's Bibliography 122247000000000044, UCLA Department of Economics.
- Leo Katz, 1953. "A new status index derived from sociometric analysis," Psychometrika, Springer;The Psychometric Society, vol. 18(1), pages 39-43, March.
- Banerjee, Abhijit & Fudenberg, Drew, 2004.
Games and Economic Behavior,
Elsevier, vol. 46(1), pages 1-22, January.
- Shachar Kariv & Syngjoo Choi & Douglas Gale, 2007.
"Social Learning in Networks: A Quantal Response Equilibrium Analysis of Experimental Data,"
843644000000000107, UCLA Department of Economics.
- Syngjoo Choi & Douglas Gale & Shachar Kariv, 2012. "Social learning in networks: a Quantal Response Equilibrium analysis of experimental data," Review of Economic Design, Springer;Society for Economic Design, vol. 16(2), pages 135-157, September.
- Sanjeev Goyal & Andrea Galeotti, 2007. "A Theory of Strategic Diffusion," Working Papers 2007.70, Fondazione Eni Enrico Mattei.
- Venkatesh Bala & Sanjeev Goyal, 1998. "Learning from Neighbours," Review of Economic Studies, Oxford University Press, vol. 65(3), pages 595-621.
When requesting a correction, please mention this item's handle: RePEc:fem:femwpa:2007.64. See general information about how to correct material in RePEc.
For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: (barbara racah)
If references are entirely missing, you can add them using this form.