Quality of Fit Measures in the Framework of Quantile Regression

Abstract. In regression experiments, to learn about the strength of the relationship between a covariate vector and a dependent variable, we propose a ‘coefficient of determination’ based on the quantiles. Such a coefficient is a ‘local’ measure in the sense that the strength is measured at a prespecified quantile level. Once estimated, it can be used, for example, to measure the relative importance of a subset of covariates in the quantile regression context. Related to this coefficient, we also propose a new ‘local’ lack‐of‐fit measure of a given parametric model. We provide some asymptotic results of the proposed measures and carry out a Monte Carlo simulation study to illustrate their use and performance in practice.     

THE IMPACT OF PRODUCT RECOVERY ON LOGISTICS NETWORK DESIGN

Efficient implementation of closed‐loop supply chains requires setting up appropriate logistics structures for the arising flows of used and recovered products. In this paper we consider logistics network design in a reverse logistics context. We present a generic facility location model and discuss differences with traditional logistics settings. Moreover, we use our model to analyze the impact of product return flows on logistics networks. We show that the influence of product recovery is very much context dependent. While product recovery may efficiently be integrated in existing logistics structures in many cases, other examples require a more comprehensive approach redesigning a company's logistics network in an integral way.     

YOUR RIGHT ARM FOR A PUBLICATION IN AER?

The time tradeoff (TTO) method is popular in medical decision making for valuing health states. We use it to elicit economists' preferences for publishing in top economic journals and for living without limbs. The economists value journal publications highly and have a clear preference among them, with the American Economic Review (AER) the most preferred. Their responses imply they would sacrifice more than half a thumb for an AER publication. These TTO results are consistent with ranking and willingness to pay results, and indicate that journal preferences are not entirely determined by impact factors or by expectations of a salary increase following a publication in a prestigious journal. (JEL A10, B41, I10)     

Probabilistic Expert Systems for Forensic Inference from Genetic Markers

We present a number of real and fictitious examples in illustration of a new approach to analysing complex cases of forensic identification inference. This is effected by careful restructuring of the relevant pedigrees as a Probabilistic Expert System. Existing software can then be used to perform the required inferential calculations. Specific complications which are readily handled by this approach include missing data on one or more relevant individuals, and genetic mutation. The method is particularly valuable for disputed paternity cases, but applies also to certain criminal cases.     

Likelihood Ratio Confidence Bands in Non–parametric Regression with Censored Data

Let ( X , Y ) be a random vector, where Y denotes the variable of interest possibly subject to random right censoring, and X is a covariate. We construct confidence intervals and bands for the conditional survival and quantile function of Y given X using a non-parametric likelihood ratio approach. This approach was introduced by Thomas & Grunkemeier (1975 ), who estimated confidence intervals of survival probabilities based on right censored data. The method is appealing for several reasons: it always produces intervals inside [0, 1], it does not involve variance estimation, and can produce asymmetric intervals. Asymptotic results for the confidence intervals and bands are obtained, as well as simulation results, in which the performance of the likelihood ratio intervals and bands is compared with that of the normal approximation method. We also propose a bandwidth selection procedure based on the bootstrap and apply the technique on a real data set.     

Community Policing and “John Schools”*

De nos jours, la police a déjà subi et continue de subir des changements dans sa philosophie et sa pratique fondamentales. Des zones de contrôle social auparavant laissées dans L'ombre par la police sont maintenant regroupées sous L'expression « police communautaire «. Le contrôle de la prostitution, bien qu'il soit traditionnellement axé sur les travailleuses du sexe, a récemment été ramené sous le parapluie de la police communautaire par le biais de méthodes parti‐culières. Cet article examine la police de quartier et son rôle élargi en prenant pour exemple les « John schools » ou programmes de traitement pour les clients de prostituées. Ces programmes, en tant que police communautaire en pratique, mettent en relief les difficultés de cette approche en général et, plus particulièrement, celles de la prostitution. Policing today has gone through and continues to undergo changes in its basic philosophy and practice. Areas of social control previously ignored by police are now included under the rhetoric of “community policing.” Control of prostitution activity, although an historical mainstay of policing directed primarily at female sex workers, has recently been subsumed under the umbrella of community policing through particular methods aimed at its control. This paper examines community policing and the expanded police role through the example of “John schools” or prostitution offender programs. As community policing in practice, such prostitution offender programs highlight the difficulties of the community policing approach generally, and the policing perspective on prostitution more specifically.     

Cultural Stereotypes and Positioning Theory

This paper addresses the application of positioning theory , a new emerging theoretical scheme on the issue of cultural stereotyping. First, a critical conceptual analysis of the words'cultural stereotype'is presented. Secondly, the basic tenets of positioning theory are outlined. Finally, it will be demonstrated how the framework of positioning theory can be used to analytically refine the concept of cultural stereotype. The main upshot of the article is that within social psychology, the concept of cultural stereotype is used in a conceptually vague and blurred way and that, with the necessary conceptual refinements, other research-agendas on stereotypes will have to be tackled if social psychologists want to contribute anything to the societal efforts of changing stereotypes.     

The Social Bases of Environmental Concern: A Review of Hypotheses, Explanations and Empirical Evidence

This paper reports an evaluation of existing knowledge regardingthe social bases of public concern with environmental quality.First, five popular hypotheses asserting relationships betweenenvironmental concern and eight demographic and social variablesare reviewed, with particular attention paid to the theoreticalexplanations offered in support of each hypothesized relationship.Second, the results of 21 relevant studies are evaluated todetermine the degree to which the empirical evidence supportsthe hypothesized relationships. Third, implications of the resultsof the review for future research are discussed.     

The management of strategic alliances: cultural resistance. Comparing the cases of a Dutch telecom operator in the Netherlands Antilles and Indonesia

Since the early 1990s, European telecom operators have expanded their activities to international markets in South America, Asia and Eastern Europe and formed complex networks of strategic alliances and joint ventures. This paper examines potential dynamics in such alliances and explores the developments in the strategic alliances of a Dutch telecom operator (KPN) in the Netherlands Antilles and Indonesia. The case studies examine how local partners responded to the cross‐cultural strategies used by KPN to manage the alliances. In particular, the studies reveal that ethnocentric cross‐cultural management strategies, used by KPN to establish a dominant position in the alliances, triggered a new awareness of the cultural identities of local telecom operators. In turn, this increased cultural awareness stimulated the patters of resistance towards KPN as the dominant partner. This paper introduces the concept of ‘ethnicization’ to describe this strategy of resistance by the less dominant partner. The paper calls for more research to understand the strategic use of cultural identity in transnational alliances.