Contributions in Merlin

We experimentally study auctions versus grandfathering in the initial assignment of pollution permits that can be traded in a secondary spot market. Low and high emitters compete for permits in the auction, while permits are assigned for free under grandfathering. In theory, trading in the spot market should erase inefficiencies due to initial mis-allocations.nIn the experiment, high emitters exercise market power in the spot market and permit holdings under grandfathering remain skewed towards high emitters. Furthermore, the opportunity costs of “free” permits are fully “passed through.” In the auction, the majority of permits are won by low emitters, reducing the need for spot-market trading. Auctions generate higher consumer surplus and slightly lower product prices in the laboratory markets. Moreover, auctions eliminate the large “windfall profits” that are observed in the treatmentnwith free, grandfathered permit allocations.

"This paper reports laboratory experiments that evaluate the performance of a flexible packagebidding format developed by the FCC, in comparison with other combinatorial formats. In general, the interest of policy makers in combinatorial auctions is justified by the laboratory data; when value complementarities are present, package bidding yields improved performance. We find clear differences among the combinatorial auction formats, however, both in terms of efficiency and seller revenue. Notably, the combinatorial clock provides the highest revenue. The FCC’s flexible package bidding format performed worse than the alternatives, which is one of the main reasons why it was not implemented."

Eating disorders are an important and growing health concern, and bulimia nervosa (BN) accounts for the largest fraction of eating disorders. Health consequences of BN are substantial and especially serious given the increasingly compulsive nature of the disorder. However, remarkably little is known about the mechanisms underlying the persistent nature of BN. Using a unique panel data set on young women and instrumental variable techniques, we document that unobserved heterogeneity plays a role in the persistence of BN, but strikingly up to two thirds is due to true state dependence. Our results, together with support from the medical literature, provide evidence that bulimia should be considered an addiction. Our findings have important implications for public policy since they suggest that the timing of the policy is crucial: preventive educational programs should be coupled with more intense (rehabilitation) treatment at the early stages of bingeing and purging behaviors. Our results are robust to different model specifications and identifying assumptions.

Consider the problem of testing s hypotheses simultaneously. In order to deal with the multiplicity problem, the classical approach is to restrict attention to procedures that control the familywise error rate (FWE). Typically, it is known how to construct tests of the individual hypotheses, and the problem is how to combine them into a multiple testing procedure that controls the FWE. The closure method of Marcus et al. (1976), in fact, reduces the problem of constructing multiple test procedures which control the FWE to the construction of single tests which control the usual probability of a Type 1 error. The purpose of this paper is to examine the closure method with emphasis on the concepts of coherence and consonance. It was shown by Sonnemann and Finner (1988) that any incoherent procedure can be replaced by a coherent one which is at least as good. The main point of this paper is to show a similar result for dissonant and consonant procedures. We illustrate the idea of how a dissonant procedure can be strictly improved by a consonant procedure in the sense of increasing the probability of detecting a false null hypothesis while maintaining control of the FWE. We then show how consonance can be used in the construction of some optimal maximin procedures.

Multi-unit ascending auctions allow for equilibria in which bidders strategically reduce their demand and split the market at low prices. At the same time, they allow for preemptive bidding by incumbent bidders in a coordinated attempt to exclude entrants fromnthe market. We consider an environment where both demand reduction and preemptivenbidding are supported as equilibrium phenomena of the ascending auction. In a series of experiments, we compare its performance to that of the discriminatory auction. Strategic demand reduction is quite prevalent in the ascending auction even when entry imposes a (large) negative externality on incumbents. As a result, the ascending auction performsnworse than the discriminatory auction both in terms of revenue and efficiency, while entrants.chances are similar across the two formats.

Every year thousands of firms are engaged in research joint ventures (RJV), where all knowledge gained through R&D is shared among members. Most of the empirical literature assumes members are non-cooperative in the product market. But many RJV members are rivals leaving open the possibility that firms may form RJVs to facilitate collusion. We examine this by exploiting variation in RJV formation generated by a policy change that affects the collusive benefits but not the research synergies associated with a RJV. We use data on RJVs formed between 1986 and 2001 together with firm-level information from Compustat to estimate a RJV participation equation. After correcting for the endogeneity of R&D and controlling for RJV characteristics and firm attributes, we find the decision to join is impacted by the policy change. We also find the magnitude is significant: the policy change resulted in an average drop in the probability of joining a RJV of 34% among telecommunications firms, 33% among computer and semiconductor manufacturers, and 27% among petroleum refining firms. Our results are consistent with research joint ventures serving a collusive function.

This paper sheds light on some unexpected consequences of health insurance regulation that may pose a big challenge to insurers’ risk management. Because mandated uniform contributions to health insurance trigger risk selection efforts risk adjustment (RA) schemes become necessary. A good deal of research into the optimal RA formula has been performed (Ellis and Van de Ven [2000]). A recent proposal has been to add ”Hospitalization exceeding three days during the previous year” as an indicator of high risk (Beck et al. [2006]). Applying the new formula to an individual Swiss health insurer, its payments into the RA scheme are postdicted to explode, reaching up to 13 percent of premium income. Its mistake had been to successfully implement Managed Care, resulting in low rates of hospitalization. The predicted risk management response is to extend hospital stays beyond three days, contrary to stated policy objectives also of the United States.

We introduce a new combinatorial auction format based on a simple, transparent pricing mechanism tailored for the hierarchical package structure proposed by Rothkopf, Pekec, and Harstad (1998) to avoid computational complexity. This combination provides the feedback necessary for bidders in multi-round auctions to discern winning bidding strategies for subsequent rounds and to coordinate responses to aggressive package bids. The resulting mechanism is compared to two leading alternatives in a series of laboratory experiments involving varying degrees of value synergies. Based on these 'wind tunnel' tests the FCC has decided to use hierarchical package bidding in the major upcoming 700MHz auction.

This paper reviews important concepts and methods that are useful for hypothesis testing. First, we discuss the Neyman-Pearson framework. Various approaches to optimality are presented, including finite-sample and large-sample optimality. Then, some of the most important methods are summarized, as well as resampling methodology which is useful to set critical values. Finally, we consider the problem of multiple testing, which has witnessed a burgeoning literature in recent years. Along the way, we incorporate some examples that are current in the econometrics literature. While we include many problems with wellknown successful solutions, we also include open problems that are not easily handled with current technology, stemming from issues like lack of optimality or poor asymptotic approximations.

We study the long-run relation between money, measured by inflation or interest rates, and unemployment. We first document in the data a positive relation between these variables at low frequencies. We then develop a framework where unemployment and money are both modeled using microfoundations based on search and bargaining theory, providing a unified theory for analyzing labor and goods markets. The calibrated model shows that money can account for a sizable fraction of trends in unemployment. We argue it matters, qualitativelynand quantitatively, whether one uses monetary theory based on search and bargaining, or an alternative ad hoc specification.