BUSINESS CYCLE ASYMMETRY: A DEEPER LOOK

This paper distinguishes two types of asymmetry in business cycles: deepness and steepness. Deepness is defined as the characteristic that troughs are further below trend than peaks are above. Most previous research has focused exclusively on steepness, which refers to cycles in which contractions are steeper than expansions. A test for deepness is proposed and applied to U.S. post-war quarterly unemployment, real GNP, and industrial production. Evidence of deepness is found for unemployment and industrial production, while the evidence for real GNP is weaker. Previous evidence of steepness in unemployment is confirmed.     

ALTERNATIVES FOR RESTRUCTURING THE RAILROADS: END-TO-END OR PARALLEL MERGERS?

The U.S. railroad industry has seen considerable merger activity over the past two decades and more mergers are expected in the near future, but little is presently known about the relative social benefits of alternative merger configurations. Using traffic data for origin-destination pairs affected by recent mergers, this paper examines the impact of end-to-end and parallel mergers on increases in the market share of merged firms. To the extent that increases in market share reflect social benefits in the form of improved service and lower costs, end-to-end mergers are found to outperform parallel mergers.     

ESTIMATING COMMUNITY STANDARDS: THE USE OF SOCIAL SCIENCE EVIDENCE IN AN OBSCENITY PROSECUTION

Elements of the legal test for obscenity of sexually explicitmaterial indicted in a criminal case are examined. A cross-sectionof residents of Mecklenburg County (Charlotte, NC) were randomlyassigned to view either one of the sexually explicit films andthe sexually explicit magazine charged in the criminal case,or a control film. Before and after the viewing, residents judgedthe materials' appeal to a prurient interest (a shameful, morbid,unhealthy interest in sex) and patent offen siveness (communitytolerance for such material). The results indicated that therespondents felt that the films and magazine did not appealto a shameful, morbid, or unhealthy interest in sex, nor didthey perceive these materials as going beyond the level of toleranceregarding depictions of sexual conduct for the average adultin that community. A lower percentage of subjects thought thecommunity tolerated the materials they had just viewed thanwhen they were asked to report on what they personally tolerated.Fewer people felt the films appealed to a shameful, morbid,or unhealthy interest in sex after they had an opportunity tosee them than before viewing. The advantages of providing jurorsin obscenity cases with information about community standardsbased on summations of personal tolerance for materials actuallycharged in these cases, rather than hypothetical judgments aboutthe community and obscenity, is discussed.     

Choice of Estimators Based on Different Observations: Modified AIC and LCV Criteria

Abstract. It is quite common in epidemiology that we wish to assess the quality of estimators on a particular set of information, whereas the estimators may use a larger set of information. Two examples are studied: the first occurs when we construct a model for an event which happens if a continuous variable is above a certain threshold. We can compare estimators based on the observation of only the event or on the whole continuous variable. The other example is that of predicting the survival based only on survival information or using in addition information on a disease. We develop modified Akaike information criterion (AIC) and Likelihood cross‐validation (LCV) criteria to compare estimators in this non‐standard situation. We show that a normalized difference of AIC has a bias equal to o ( n ^{? 1} ) if the estimators are based on well‐specified models; a normalized difference of LCV always has a bias equal to o ( n ^{? 1} ). A simulation study shows that both criteria work well, although the normalized difference of LCV tends to be better and is more robust. Moreover in the case of well‐specified models the difference of risks boils down to the difference of statistical risks which can be rather precisely estimated. For ‘compatible’ models the difference of risks is often the main term but there can also be a difference of mis‐specification risks.     

HEDONIC IMPUTATION AND THE PRICE INDEX PROBLEM: AN APPLICATION TO HOUSING

In this study, we show how use of the hedonic imputation method complicates the price index problem. In addition to the usual choice between formulas such as Fisher and Törnqvist, the fact that index compilers have some discretion over which prices are imputed implies that it is necessary to choose as well between different varieties of each formula. The functional form of the hedonic model must also be taken into account. We illustrate the importance of these issues in a housing context using house price data for three regions in Sydney over a 3‐yr period. (JEL C43, E31, O47, R31)     

MIXED ASSEMBLY AND DISASSEMBLY OPERATIONS FOR REMANUFACTURING

In this paper we consider the problem of designing a mixed assembly‐disassembly line for remanufacturing. That is, parts from the disassembly and repair of used products can be used to build “new” products. This is a problem common to many OEM remanufacturers, such as Xerox or Kodak. We study two main configurations, under the assumption that the disassembly sequence is exactly the reverse of the assembly sequence. Under a parallel configuration, there exist two separate dedicated lines, one for assembly and one for disassembly, which are decoupled by buffers—from both disassembly operations, which have preference, as well as parts from an outside, perfectly reliable supplier. Under a mixed configuration, the same station is used for both disassembly and assembly of a specific part. The problem is studied using GI/G/c networks, as well as simulation. Due to a loss of pooling, we conclude that the parallel configuration outperforms the mixed line only when the variability of both arrivals and processing time are significantly higher for disassembly and remanufacturing than for assembly. Via a simulation, we explore the impact of having advanced yield information for the remanufacturing parts. We find that advanced yield information generally improves flow times; however, there are some instances where it lengthens flow times.