Games and Economic Behavior
Опубликовано на портале: 25-11-2004
David Myatt, Chris C. Wallace
Games and Economic Behavior.
2004.
Vol. 48.
No. 1.
P. 124-138.
Equilibrium selection in coordination games has generated a large literature. Kandori,
Mailath and Rob (1993) and Young (1993) studied dynamic models of aggregate behaviour
in which agents choose best responses to observations of population play. Crucially,
infrequent mistakes (`mutations`) allow agents to take actions contrary to current
trends and prevent initial configurations from determining long run play. An alternative
approach is offered here: Harsanyian trembles are added to agents` payoffs so that
with some probability it is optimal to act against the flow of play. The long run
distribution of population behaviour is characterised - modes correspond to stable
Bayesian Nash equilibria. Allowing the variance of payoff trembles to vanish, via
a purification process, a single equilibrium is played almost always in the long
run. Kandori et al and Young show that the number of contrarian actions required
to escape an equilibrium determines selection; here, the likelihood that such actions
are taken is of equal importance.


Learning to Play Bayesian Games [статья]
Опубликовано на портале: 14-02-2005
Eddie Dekel, Drew Fudenberg, David Knudsen Levine
Games and Economic Behavior.
2004.
Vol. 46.
No. 2.
P. 282-303.
This paper discusses the implications of learning theory for the analysis of games
with a move by Nature. One goal is to illuminate the issues that arise when modeling
situations where players are learning about the distribution of Nature's move as
well as learning about the opponents' strategies. A second goal is to argue that
quite restrictive assumptions are necessary to justify the concept of Nash equilibrium
without a common prior as a steady state of a learning process.

