Abstract
Given a finite state space and common priors, common knowledge of the identity of an agent with the minimal (or maximal) expectation of a random variable implies ‘consensus’, i.e., common knowledge of common expectations. This ‘extremist’ statistic induces consensus when repeatedly announced, and yet, with n agents, requires at most log2 n bits to broadcast.
Similar content being viewed by others
REFERENCES
Aumann, R. (1976), Agreeing to disagree, The Annals of Statistics 4(6): 1236–1239.
Cover, T. and Thomas, J. (1991), Elements of Information Theory. New York: John Wiley & Sons.
Geanakoplos, J. and Polemaarchakis, H. (1982), We can't disagree forever, Journal of Economic Theory 28: 192–200.
Hanson, R. (1996), Correction to McKelvey and Page, ‘Public and private information: An experimental study of information pooling’, Econometrica 64(5): 1223–1224.
McKelvey R. and Page, T. (1986), Common knowledge, consensus, and aggregate information, Econometrica 54(1): 109–127.
McKelvey, R. and Page, T. (1990), Public and private information: An experimental study of information pooling, Econometrica 58(6): 1321–1339.
Nielsen, L.T., Brandenburger, A., Geanakoplos, J., McKelvey, R., and Page, T. (1990), Common knowledge of an aggregate of expectations, Econometrica 58(5): 1235–1239.
Nielsen, L.T. (1984), Common knowledge, communication, and convergence of beliefs, Mathematical Social Sciences 8: 1–14.
Nielsen, L.T. (1995), Common knowledge of a multivariate aggregate statistic, International Economic Review 36(1).
Sebenius, J., and Geanakoplos, J. (1983), Don't bet on it: Contingent agreements with asymmetric information, Journal of the American Statistical Association 78: 424–426.
Rights and permissions
About this article
Cite this article
Hanson, R.D. Consensus By Identifying Extremists. Theory and Decision 44, 293–301 (1998). https://doi.org/10.1023/A:1004918905650
Issue Date:
DOI: https://doi.org/10.1023/A:1004918905650