Assessing Preference Change on the US Supreme Court

The foundation upon which accounts of policy-motivated behaviorof Supreme Court justices are built consists of assumptionsabout the policy preferences of the justices. To date, mostscholars have assumed that the policy positions of Supreme Courtjustices remain consistent throughout the course of their careersand most measures of judicial ideology—such as Segal andCover scores—are time invariant. On its face, this assumptionis reasonable; Supreme Court justices serve with life tenureand are typically appointed after serving in other politicalor judicial roles. However, it is also possible that the worldviews,and thus the policy positions, of justices evolve through thecourse of their careers. In this article we use a Bayesian dynamicideal point model to investigate preference change on the USSupreme Court. The model allows for justices' ideal points tochange over time in a smooth fashion. We focus our attentionon the 16 justices who served for 10 or more terms and completedtheir service between the 1937 and 2003 terms. The results arestriking—14 of these 16 justices exhibit significant preferencechange. This has profound implications for the use of time-invariantpreference measures in applied work.     

The role of boundary solutions in principal-agent problems of the Holmström-Milgrom type

The paper extends the Holmström-Milgrom [B. Holmström, P. Milgrom, Aggregation and linearity in the provision of intertemporal incentives, Econometrica 55 (1987) 303-328] analysis of intertemporal incentive provision to allow for the implementation of actions on the boundary of the feasible set. Boundary actions provide the principal with some freedom in choosing incentive schemes. This can be used to reduce premia. The paper characterizes optimal incentive schemes for the continuous-time Brownian-motion model and its discrete-time approximations. Linearity of incentive schemes in “accounts” is confirmed. However, for models with effort costs depending only on mean returns, the availability of boundary actions destroys the linearity of optimal incentive schemes in profits.     

Office triage and the physician's supply curve

This paper contains a theoretical and empirical model of the physician firm. The utility maximizing physician chooses the number of hours of labor to supply and the mix between patient visits and time per visit. Theory suggests that a serious specification error may occur if one estimates the labor supply curve and patient demand curve without simultaneously estimating the mix between patient visits and time per visit. A Chi-Square specification test reveals that this “triage” model statistically dominates the simple supply/demand model. Estimation results indicate relevant backward-bending labor and negatively sloped service supply functions.     

Does Child Labour Displace Schooling? Evidence on Behavioural Responses to an Enrollment Subsidy

It is often argued that child labour comes at the expense of schooling and so perpetuates poverty for children from poor families. To test this claim we study the effects on children's labour force participation and school enrollments of the pure school-price change induced by a targeted enrollment subsidy in rural Bangladesh. Our theoretical model predicts that the subsidy increases schooling, but its effect on child labour is ambiguous. Our empirical model indicates that the subsidy increased schooling by far more than it reduced child labour. Substitution effects helped protect current incomes from the higher school attendance induced by the subsidy.     

How Do Banks Determine Capital? Evidence from Germany

Abstract. We analyse whether the determinants of capital found in the previous literature hold for the special German banking sector comprising three characteristic banking groups including savings banks, cooperative banks and other banks, which differ regarding their ownership and their access to the capital market. Through the use of accounting data from German banks between 1992 and 2001 we find evidence in accordance with the buffer theory of capital for all German banking groups. Furthermore, we also detect some remarkable differences between the three banking groups regarding their determination of capital due to institutional characteristics.     

Exit Deterrence

This paper is the first to provide a general context whereby potential entry can lead incumbent firms to permanently reduce the intensity of competition in a market. All previous results found that potential entry would lead to lower prices and greater competition. Examining markets where entry occurs by the acquisition of access rights from an existing incumbent, we demonstrate that, where competitive choices are strategic complements, a more efficient entrant may be unable to acquire those rights from a less efficient incumbent due to the unilateral accommodating behavior of the efficient incumbent. Similarly, such accommodating behavior may deter efficient investment by an incumbent. These results have implications as to how economists view potential entry and its benefits.     

CONVERTIBLE BOND PRICING MODELS

Convertible bonds are an important segment of the corporate bond market, with worldwide outstandings approaching US$235 billion. Simple pricing models value a convertible bond as being equivalent to a straight bond with an embedded option that enables the bond holder to convert to a specific amount of common stock. The straight bond is subject to both interest rate and credit risk, whereas the option to convert is dependent on the underlying stock price, which exposes the convertible bond holder to equity risk. The complexity of these features means that convertible bonds tend to be treated casually in major derivatives and corporate finance textbooks. This paper presents a survey of the theoretical and empirical aspects of convertible bond pricing. The limitations of these studies are highlighted to identify those areas of research that may improve the valuation process and facilitate the application of these securities for corporate financing.     

TESTING POVERTY LINES

In theory, a poverty line can be defined as the cost of a common (inter‐personally comparable) utility level across a population. But how can one know if this holds in practice? For groups sharing common consumption needs but facing different prices, the theory of revealed preference can be used to derive testable implications of utility consistency knowing only the “poverty bundles” and their prices. Heterogeneity in needs calls for extra information. We argue that subjective welfare data offer a credible means of testing utility consistency across different needs groups. A case study of Russia's official poverty lines shows how revealed preference tests can be used in conjunction with qualitative information on needs heterogeneity. The results lead us to question the utility consistency of Russia's official poverty lines.     

Which school systems sort weaker students into smaller classes? International evidence

We examine whether the sorting of high- and low-achieving students into classes of different sizes results in a regressive or compensatory pattern of class sizes for 18 national school systems. Sorting effects are identified by subtracting the causal effect of class size on performance from their total correlation. Our empirical results reveal strongly compensatory patterns of sorting within and especially between schools in many countries. Only the United States, which has a decentralized education finance and considerable residential mobility, exhibits regressive between-school sorting. Between-school sorting is more compensatory in systems with ability tracking. Within-school sorting is more compensatory where administrators rather than teachers assign students to classrooms.     

Non-manipulable domains for the Borda count

Summary. We characterize the preference domains on which the Borda count satisfies Arrows independence of irrelevant alternatives condition. Under a weak richness condition, these domains are obtained by fixing one preference ordering and including all its cyclic permutations (Condorcet cycles). We then ask on which domains the Borda count is non-manipulable. It turns out that it is non-manipulable on a broader class of domains when combined with appropriately chosen tie-breaking rules. On the other hand, we also prove that the rich domains on which the Borda count is non-manipulable for all possible tie-breaking rules are again the cyclic permutation domains.Received: 24 November 2003, Revised: 12 December 2004, JEL Classification Numbers: D71. Correspondence to: Clemens PuppeThe third author gratefully acknowledges the financial support from the Deutsche Forschungsgemeinschaft (DFG), Graduiertenkolleg 629 at the University of Bonn and from the Hungarian Scientific Research Fund (OTKA F 043496).