This study is the first to attempt to isolate a relationship between cognitive activity and equilibration to a Nash Equilibrium. Subjects, while undergoing fMRI scans of brain activity, participated in second price auctions against a single competitor following predetermined strategy that was unknown to the subject. For this auction there is a unique strategy that will maximize the subjects' earnings, which is also a Nash equilibrium of the associated game theoretic model of the auction. As is the case with all games, the bidding strategies of subjects participating in second price auctions most often do not reflect the equilibrium bidding strategy at first but with experience, typically exhibit a process of equilibration, or convergence toward the equilibrium. This research is focused on the process of convergence. In the data reported here subjects participated in sixteen auctions, after which all subjects were told the strategy that will maximize their revenues, the theoretical equilibrium. Following that announcement, sixteen more auctions were performed. The question posed by the research concerns the mental activity that might accompany equilibration as it is observed in the bidding behavior. Does brain activation differ between equilibrated and non-equilibrated in the sense of a bidding strategy? If so, are their differences in the location of activation during and after equilibration? We found significant activation in the frontal pole especially in Brodmann's area 10, the anterior cingulate cortex, the amygdala and the basal forebrain. There was significantly more activation in the basal forebrain and the anterior cingulate cortex during the first sixteen auctions than in the second sixteen. The activity in the amygdala shifted from the right side to the left after the solution was given.
In this paper we have examined data from the Survey of Professional Forecasters. We study nominal GDP, the unemployment rate, the Treasury bill rate and the implicit price deflator beginning with the first quarter of 1992. Forecasts for a single time period appear several times in consecutive forecasts in the survey. We study the revision of forecasts for a fixed points in time. We find that the forecasts were not unbiased, but they were biased in directions one would expect, ex post. There is strong dependence of revisions of expectations on the most recently observed one step forecast errors. For most series, lagged innovations do not enter the regression equations significantly and constant terms are not significantly different from zero. Most forecasters seem to be using information on several series in their forecasts.
This paper reports experimental tests of three search equilibrium models. These models which differ only in the search strategies available to the buyers have qualitatively different predictions, that is, equilibria: price distributions, single price equilibria at the competitive price and at the monopoly price and two price equilibria. The experimental outcomes generally were consistent with the models' predictions. This suggests that debate on the utility of this class of models should shift to the realism of the models' assumptions rather than focus on their ability to characterize market outcomes. Also, since the basic models have been validated, the project of analyzing experimentally the results of relaxing some of their assumptions seems worthwhile.