Traders' values and information typically consist of both private and common-value elements. In such environments, full allocative efficiency is impossible when the private rate of information substitution differs from the social rate (Jehiel and Moldovanu, 2001). We link this impossibility result to a failure of the efficient market hypothesis, which states that prices adequately reflect all available information (Fama, 1970, 1991). The intuition is that if prices were able to reveal all information then the common value would simply shift traders' private values by a known constant and full allocative efficiency would result. In a series of laboratory experiments we study price formation in markets with private and common values. Rational expectations, which form the basis for the efficient market hypothesis, predict that the introduction of common values has no adverse consequences for allocative and informational efficiency. In contrast, a "private" expectations model in which traders' optimal behavior depends on both their private and common-value information predicts that neither full allocative nor full informational efficiency is possible. We test these competing hypotheses and find that the introduction of common values lowers allocative efficiency by 28% on average, as predicted by the private expectations model, and that market prices differ significantly and substantially from their rational expectation levels. Finally, a comparison of observed and predicted payoffs suggests that observed behavior is close to the equilibrium predicted by the private expectations model.
Few would deny that there is a strong link between the health of a country’s banks and its public finances. With that in mind, this column argues that the banking system can learn from banking deregulation in the US, with knock on effects for Europe’s sovereign debt crisis.
This paper reports results from a series of laboratory experiments designed to evaluate the impact of exposure risk on market performance. Exposure risk arises when there are complementarities between trades, e.g. when the purchase of a new house requires selling the old one. The continuous double auction (CDA), which has proven to be remarkably effective in a wide variety of settings, performs poorly in a treatment with high exposure risk: overall market efficiency is only 20% and there are many instances of no trade. In a parallel treatment with lower exposure risk, efficiency under the CDA is higher (55%) but is dominated, for instance, by a top-trading-cycles procedure that uses no money. The CDA's poor performance does not depend on whether house values are private information or common knowledge, indicating that exposure risk is due to strategic uncertainty not objective uncertainty about others' preferences. We introduce a simple package market and show that it effectively resolves exposure risk: efficiency levels are 82% and 89% respectively for the low and high exposure treatments. The proposed package market is a simple extension of the CDA and could potentially be applied in a variety contexts.
Facial emotions express our internal states and are fundamental in social interactions. Here we explore whether the repetition of unattended facial emotions builds up a predictive representation of frequently encountered emotions in the visual system. Participants (n = 24) were presented peripherally with facial stimuli expressing emotions while they performed a visual detection task presented in the center of the visual field. Facial stimuli consisted of four faces of different identity, but expressed the same emotion (happy or fearful). Facial stimuli were presented in blocks of oddball sequence (standard emotion: p = 0.9, deviant emotion: p = 0.1). Event-related potentials (ERPs) to the same emotions were compared when the emotions were deviant and standard, respectively. We found visual mismatch negativity (vMMN) responses to unattended deviant emotions in the 170–360 ms post-stimulus range over bilateral occipito-temporal sites. Our results demonstrate that information about the emotional content of unattended faces presented at the periphery of the visual field is rapidly processed and stored in a predictive memory representation by the visual system. We also found evidence that differential processing of deviant fearful faces starts already at 70–120 ms after stimulus onset. This finding shows a ‘negativity bias’ under unattended conditions. Differential processing of fearful deviants were more pronounced in the right hemisphere in the 195–275 ms and 360–390 ms intervals, whereas processing of happy deviants evoked larger differential response in the left hemisphere in the 360–390 ms range, indicating differential hemispheric specialization for automatic processing of positive and negative affect.
This study compares individual preferences across incentives (i.e., hypothetical vs. real incentives) and over time (i.e. elicitation at two different points in time) in a choice experiment involving charitable donating decisions. We provide evidence of hypothetical bias but little evidence of instability of individual giving. There is significant heterogeneity in individual preferences, with real incentives either dampening or pronouncing the observed donating behaviour. Neither hypothetical bias nor instability is observed when we examine the propensity of individuals to make internally consistent decisions over identical choices.
This paper examines whether and how cheap talk communication can facilitate within-group coordination when two unequal sized groups compete for a prize that is shared equally among members of the winning group, regardless of their (costly) contributions to the group’s success. We find that allowing group members to communicate before making contribution decisions improves coordination. To measure how much miscoordination remains, we employ a control treatment where miscoordination is eliminated by asking group members to reach a unanimous contribution decision. Average group contributions are not significantly different in this control treatment. Cheap talk communication thus completely solves miscoordination within groups and makes group members act as a single agent. Furthermore, it is the larger group that benefits from communication at the expense of the smaller group. Finally, content analysis of group communication reveals that after the reduction of within-group strategic uncertainty, groups reach self-enforcing agreements on how much to contribute, designate specific contributors according to a rotation scheme, and quickly discover the logic of the mixed-strategy equilibrium.
Governments all over the world have invested tens of billions of dollars in car scrappage programs to fuel the economy in 2009. We investigate the German case using a unique micro transaction dataset covering the years 2007 to 2010. Our focus is on the incidence of the subsidy, i.e., we ask how much of the € 2,500 buyer subsidy is captured by the supply-side through an increase in selling prices.
Using regression analysis, we find that average prices in fact decreased for subsidized buyers in comparison to non-subsidized ones, suggesting that eventually subsidized customers benefitted by more than the subsidy amount. However, the incidence was heterogeneous across price segments. Subsidized buyers of cheap cars paid more than comparable buyers who did not receive the subsidy, e.g. for cars of € 12,000 car dealers reaped about 8% of the scrappage prime. The opposite was true for more expensive cars, e.g. subsidized buyers of cars of € 32,000 were granted an extra discount of about € 1,100. For cars priced about € 18,000, we find no price discrimination, i.e., in this price segment consumers fully captured the transfer. Our results can be explained by optimizing behavior on the supply-side both in the lower and upper price segments. The results are extremely robust to extensive sensitivity checks.
