Whose Opinion Counts? Political Processes and the Implementation Problem
We augment the mechanism used in Nash implementation with a political process that collects the opinions of a subset of individuals with a xed probability distribution. The outcome is a function of only the collected opinions. We show that the necessary - and sometimes sufficient - condition for implementation by a specic political process can be either weaker or stronger than Maskin monotonicity. We study three such processes: oligarchy, oligarchic democracy and random sampling. Oligarchy collects only the opinions of the oligarchs (a strict subset of the individuals). We present a Nash implementable social choice rule (SCR) that cannot be implemented by any oligarchy. Oligarchic democracy "almost always" collects the opinions of the oligarchs but sometimes, there is a referendum (i.e., everyone's opinions are collected). We show that in economic environments, every Nash implementable SCR can be implemented by oligarchic democracy in which any three individuals act as oligarchs. In random sampling, a sample of opinions are collected randomly. We show that in economic environments, every Nash implementable SCR can be implemented by randomly sampling opinions of 4 individuals. We also provide necessary and sufficient conditions for implementation when the planner has the exibility to choose any political process.
References listed on IDEAS
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.:
- Saijo, Tatsuyoshi, 1988. "Strategy Space Reduction in Maskin's Theorem: Sufficient Conditions for Nash Implementation," Econometrica, Econometric Society, vol. 56(3), pages 693-700, May.
- Danilov, Vladimir, 1992. "Implementation via Nash Equilibria," Econometrica, Econometric Society, vol. 60(1), pages 43-56, January.
- Benoît, Jean-Pierre & Ok, Efe A., 2008. "Nash implementation without no-veto power," Games and Economic Behavior, Elsevier, vol. 64(1), pages 51-67, September.
- Maskin, Eric & Sjostrom, Tomas, 2002.
Handbook of Social Choice and Welfare,
in: K. J. Arrow & A. K. Sen & K. Suzumura (ed.), Handbook of Social Choice and Welfare, edition 1, volume 1, chapter 5, pages 237-288
- Matthew 0. Jackson, 1989.
"Implementation in Undominated Strategies - A Look at Bounded Mechanisms,"
833, Northwestern University, Center for Mathematical Studies in Economics and Management Science.
- Jackson, Matthew O, 1992. "Implementation in Undominated.Strategies: A Look at Bounded Mechanisms," Review of Economic Studies, Wiley Blackwell, vol. 59(4), pages 757-75, October.
- Maskin, Eric, 1999.
"Nash Equilibrium and Welfare Optimality,"
Review of Economic Studies,
Wiley Blackwell, vol. 66(1), pages 23-38, January.
- Eric Maskin, 1998. "Nash Equilibrium and Welfare Optimality," Harvard Institute of Economic Research Working Papers 1829, Harvard - Institute of Economic Research.
- Olivier Bochet, 2007.
"Nash Implementation with Lottery Mechanisms,"
Social Choice and Welfare,
Springer, vol. 28(1), pages 111-125, January.
- Dirk Bergemann & Stephen Morris, 2005.
"Ex Post Implementation,"
784828000000000018, UCLA Department of Economics.
- Dirk Bergemann & Stephen Morris, 2005. "Ex Post Implementation," Cowles Foundation Discussion Papers 1502, Cowles Foundation for Research in Economics, Yale University.
- Dirk Bergemann & Stephen Morris, 2006. "Ex Post Implementation," Levine's Bibliography 122247000000001110, UCLA Department of Economics.
- Yamato, Takehiko, 1992. "On nash implementation of social choice correspondences," Games and Economic Behavior, Elsevier, vol. 4(3), pages 484-492, July.
- Moore, John & Repullo, Rafael, 1990. "Nash Implementation: A Full Characterization," Econometrica, Econometric Society, vol. 58(5), pages 1083-99, September.
- Palfrey, Thomas R & Srivastava, Sanjay, 1991. "Nash Implementation Using Undominated Strategies," Econometrica, Econometric Society, vol. 59(2), pages 479-501, March.
When requesting a correction, please mention this item's handle: RePEc:aah:aarhec:2011-06. 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: ()
If references are entirely missing, you can add them using this form.