Knowledge that Transforms

We propose a procedure for estimating the critical values of the extended Kolmogorov-Smirnov tests of Stochastic Dominance of arbitrary order in the general K-prospect case. We allow for the observations to be serially dependent and, for the first time, we can accommodate general dependence amongst the prospects which are to be ranked. Also, the prospects may be the residuals from certain conditional models, opening the way for conditional ranking. We also propose a test of Prospect Stochastic Dominance. Our method is based on subsampling and we show that the resulting tests are consistent and powerful against some N−1/2 local alternatives. We also propose some heuristic methods for selecting subsample size and demonstrate in simulations that they perform reasonably. We describe an alternative method for obtaining critical values based on recentring the test statistic and using full-sample bootstrap methods. We compare the two methods in theory and in practice.

ABSTRACT. This paper proves that the monotonicity of bidding strategies together with the rationality of bidders implies that the winning bid in a first price auction converges to the competitive equilibrium price as the number of bidders increases (Wilson (1977)). Instead of analyzing the symmetric Nash equilibrium, we examine rationalizable strategies (Bernheim (1984) and Pearce (1984)) among the set of monotonic bidding strategies to prove that any monotonic rationalizable bidding strategy must be within a small neighborhood of the “true ” valuation of the object, conditioned on the signal received by the bidder. We obtain an information aggregation result similar to Wilson (1977), while dispensing with almost all symmetric assumptions and using a milder solution concept than the Nash equilibrium. In particular, if every bidder is ex ante identical, then any rationalizable bidding strategy must be within a small neighborhood of the symmetric Nash equilibrium. In a symmetric first price auction, the symmetry of outcomes is implied rather than assumed.

Contrary to conventional wisdom, a right to silence can reduce wrongful convictions of innocent suspects who tell police the truth, and may reduce the overall conviction rate without affecting the confession rate. We establish these conclusions by modelling interrogation as a game in which suspects are privately informed of their type, but do not know the content of witness reports. Our model has testable implications which distinguish it from competing models. The best data rejects competing models, but does not reject our model. Copyright 2005, Wiley-Blackwell.

We study how securities and issuance mechanisms can be designed to mitigate the adverse impact of market imperfections on liquidity. In our model, asset owners seek to obtain liquidity by selling claims contingent on privately observed future cash-flows. Liquidity suppliers can be competitive or strategic. In the optimal trading mechanism associated with an arbitrary given security, issuers with low cash-flows sell their entire holdings of the security, while issuers with high cash-flows are typically excluded from trade. By designing the security optimally, issuers can avoid exclusion altogether. We show that the optimal security is debt. Because of its low informational sensitivity, debt mitigates the adverse selection problem. Furthermore, by pooling all issuers with high cash-flows, debt also reduces the ability of a monopolistic liquidity supplier to exclude them from trade in order to better extract rents from issuers with lower cash-flows.

The observation that liquidations are concentrated in recessions has long been the subject of controversy. One view holds that liquidations are beneficial in that they result in increased restructuring. Another view holds that this rise in restructuring is costly since liquidations are privately inefficient and essentially wasteful. This paper proposes an alternative perspective. On the basis of a combination of theory with empirical evidence on gross job flows and on financial and labour market rents, we find that, cumulatively, recessions result in reduced rather than increased restructuring, and that this is likely to be socially costly once we consider inefficiencies on both the creation and destruction margins. Copyright 2005, Wiley-Blackwell.

To study the detailed location patterns of industries, and particularly the tendency for industries to cluster relative to overall manufacturing, we develop distance-based tests of localization. In contrast to previous studies, our approach allows us to assess the statistical significance of departures from randomness. In addition, we treat space as continuous instead of using an arbitrary collection of geographical units. This avoids problems relating to scale and borders. We apply these tests to an exhaustive U.K. data-set. For four-digit industries, we find that (i) 52% of them are localized at a 5% confidence level, (ii) localization mostly takes place at small scales below 50 km, (iii) the degree of localization is very skewed, and (iv) industries follow broad sectoral patterns with respect to localization. Depending on the industry, smaller establishments can be the main drivers of both localization and dispersion. Three-digit sectors show similar patterns of localization at small scales as well as a tendency to localize at medium scales.

We model externality abatement as an implementation problem. A social planner would like to ensure efficient behaviour among a group of agents whose actions are sources of externalities. However, the planner has limited information about the agents' preferences, and is unable to distinguish individual agents except through their action choices. We prove that if a concavity condition on aggregate payoffs is satisfied, the planner can guarantee that efficient behaviour is globally stable under a wide range of behaviour adjustment processes by administering a variable pricing scheme. Through a series of applications, we show that the concavity condition is naturally satisfied in settings involving negative externalities. We conclude by contrasting the performance of the pricing mechanism with that of a mechanism based on direct revelation and announcement dependent forcing contracts.

Abstract: Existing empirical studies are typically unable to sort out the direction of causality between poverty and violent crime in less developed countries. This study uses local rainfall variation – which is plausibly exogenous and closely related to income – to estimate the impact of negative income shocks on murder in 67 Tanzanian villages across eleven years. Extreme rainfall leads to a large statistically significant increase in the murder of “witches ” – typically elderly women killed by relatives – but not in other types of murders. The results are consistent with a model in which households near subsistence kill (or expel) relatively unproductive elderly household members to safeguard the nutritional status of other members. The theory is bolstered by the fact that most killings take place in low socio-economic status villages during the so-called “hungry season ” of the year, and most victims are from poor households. The results provide novel evidence on the role of poverty as a cause of violent crime.

We use a new approach to study questions in political economy that relies on data on the subjective well-being of a large sample of people living in the OECD over the period 1975–1992. Controlling for the personal characteristics of the respondents, year and country fixed effects and country-specific time trends, we find that the data describe social happiness functions for left-wing and right-wing individuals where inflation and unemployment enter negatively. We use these functions to test the root assumption of partisan business cycle models. The evidence is consistent with the hypothesis that left-wing individuals care more about unemployment relative to inflation than right-wingers. Interestingly, we find that individuals declare themselves to be happier when the party they support is in power, even after controlling for macroeconomic variables. The effect of politics is large. Finally, we find that these partisan differences cannot be traced back to income differences. That is, it is misleading to assume—as it is done in the previous literature—that the poor (rich) behave similarly to the left (right). For example, inflation and unemployment do not have differential effects across rich and poor and the happiness levels of these two groups are unaffected by the identity of the party in power. Our findings are hard to explain using median voter models but are to be expected in a partisan world.

We model an OLG economy where productivity growth comes from two alternative sources: process innovation and learning-by-doing. There is a trade-off between the two in so far as frequent technological updates reduce the scope for learning on existing technologies. A conflict is shown to arise between the young and the old, because the former favor innovation while the latter prefer learning. We model the interaction between different generations and short-lived policy makers as a dynamic common agency problem, where competing generations invest a certain amount of resources to lobby either for the maintainance of the current technology or the adoption of a new one. By focusing on truthful Markov perfect equilibria, we characterize the political equilibrium and show its dependence on the underlying technological parameters.