Purification and roulette wheels

Author(s)
Konrad Podczeck, Michael Greinecker
Abstract

We use concepts introduced by Aumann more than 30 years ago to throw new light on purification in games with extremely dispersed private information. We show that one can embed payoff-irrelevant randomization devices in the private information of players and use these randomization devices to implement mixed strategies as deterministic functions of the private information. This approach gives rise to very short and intuitive proofs for a number of purification results that previously required sophisticated methods from functional analysis or nonstandard analysis. We use our methods to prove the first general purification theorem for games with private information in which a player’s payoffs can depend in arbitrary ways on events in the private information of other players and in which we allow for shared information in a general way.

Organisation(s)
Department of Economics
External organisation(s)
Leopold-Franzens-Universität Innsbruck
Journal
Economic Theory
Volume
58
Pages
255-272
No. of pages
18
ISSN
0938-2259
DOI
https://doi.org/10.1007/s00199-014-0815-1
Publication date
02-2015
Peer reviewed
Yes
Austrian Fields of Science 2012
502047 Economic theory
Keywords
ASJC Scopus subject areas
Economics and Econometrics
Portal url
https://ucris.univie.ac.at/portal/en/publications/purification-and-roulette-wheels(4ef909de-cd55-49ad-971e-e4eed89da76e).html