Adaptive Jonckheere-type tests for ordered alternatives

Testing against ordered alternatives in the c -sample location problem plays an important role in statistical practice. The parametric test proposed by Barlow et al .-in the following, called the 'B-test'-is an appropriate test under the model of normality. For non-normal data, however, there are rank tests which have higher power than the B-test, such as the Jonckheere test or so-called Jonckheere-type tests introduced and studied by Buning and Kossler. However, we usually have no information about the underlying distribution. Thus, an adaptive test should be applied which takes into account the given data set. Two versions of such an adaptive test are proposed, which are based on the concept introduced by Hogg in 1974. These adaptive tests are compared with each of the single Jonckheere-type tests in the adaptive scheme and also with the B-test. It is shown via Monte Carlo simulation that the adaptive tests behave well over a broad class of symmetric distributions with short, medium and long tails, as well as for asymmetric distributions.     

The twelve-hour shift in the north American mini-steel industry

The twelve-hour shift is now widely practiced in the chemical and petroleum industries but has not spread to many other continuous operations, in part because of the belief that the stress and heat in heavy metals precluded its use there. The innovators who created the mini-steel industry, however, have adopted this shift widely. This article, based principally upon a 1988–89 survey, supplemented in 1990 by a survey of additional Canadian plants, examines the experience of the mini-steel industry with the twelve-hour shift and finds that managements consider it a “definite plus,” particularly in terms of employee relations. The posture of the United Steelworkers, is, however, ambivalent, with reservations about the shift by national and some local officials, and support by other local officials. Professor Emeritus of Management and former Director, Industrial Research Unit, and Chairman, Labor Relations Council. David O. Northrup conducted the interviews and made important suggestions regarding the study.     

Fathers-The Secondary Partners: Professional Perceptions and Fathers' Reflections

SUMMARY. The following is an account of a research project exploring the recollections of seven fathers at the time of the birth of their children with Down's Syndrome. It discusses the disclosure of diagnosis and subsequent contacts the fathers made both professionally and socially during the period following both in the hospital and at home. This is combined with the personal recollections of one father, not part of the original study, whose child was born with special needs. The implications for both professional practice and fathers are highlighted. Whilst there is an acknowledgement that the project was small scale, the conclusions will raise challenging issues for further discussion both among professionals and individual members of families.     

Robust analysis of variance

SUMMARY For the c -sample location problem with equal and unequal variances, we compare the classical F -test and its robustified version-the Welch test-with some nonparametric counterparts defined for two-sided and one-sided ordered alternatives, such as trend and umbrella alternatives. A new rank test for long-tailed distributions is proposed. The comparison is referred to level alpha and power beta of the tests, and is carried out via Monte Carlo simulation, assuming short-, medium- and long-tailed as well as asymmetric distributions. It turns out that the Welch test is the best one in the case of unequal variances but in the case of equal variances special non-parametric tests are to prefer.     

Analyzing the Efficient Execution of In‐Store Logistics Processes in Grocery Retailing—The Case of Dairy Products

In this article, we examine in‐store logistics processes for handling dairy products, from the incoming dock to the shelves of supermarkets and hypermarkets. The efficient execution of the in‐store logistics related to such fast‐moving, sensitive, and essential items is challenging and crucial for grocery retailers' sales, profits, and image. In our empirical study, we survey in‐store logistics processes in 202 grocery supermarkets and hypermarkets belonging to a major retail chain in central Europe. Using a data envelopment analysis (DEA) and simulation, we facilitate process benchmarking. In particular, we identify ways of improving in‐store logistics processes by showing the performance impacts of different managerial strategies and tactics. The DEA results indicate different efficiency levels for different store formats; the hybrid store format of the small hypermarket exhibits a comparatively worse performance in the analyzed execution of in‐store logistics processes. The process simulation analysis reveals that the strategic and tactical design of in‐store logistics processes (such as store locations/layouts, capacity management, reorder time, order period, and safety stock factors) lead to substantial service performance improvements (such as higher on‐shelf availability combined with reduced inventory obsolescence costs). The results also show marginal improvements in the performance figures when delivery delays and damage to products are reduced.     

Prek?re Einkommenslagen in Deutschland. Ein Ost-West-Vergleich 1996–2002

Zusammenfassung Der Beitrag untersucht die Verteilung der ?quivalenzgewichteten Nettoeinkommen von Haushalten und Lebensgemeinschaften in West- und Ostdeutschland für die Zeit von 1996 bis 2002 auf der Grundlage der Daten des Mikrozensus. Die Untersuchung gliedert sich in einen deskriptiven Teil, der eindimensionale Ma?e zur Einkommensverteilung und zur Messung der Ungleichheit diskutiert, und in einen zweiten Teil, in dem auf der Basis eines Logit-Modells Determinanten bestimmt werden, die für prek?re Lebens- und Einkommenslagen urs?chlich sein k?nnen. Ein besonderes Gewicht wird hierbei auf unterschiedliche Lebensformen und die Anzahl der Kinder gelegt. Die Ergebnisse zeigen ein deutlich h?heres Armutsrisiko für Lebensgemeinschaften/Familien mit Kindern im Vergleich zu kinderlosen Paaren.