Statistical inference through AFT model for biotechnical systems

The objective of this paper is to model the phenomenon of degradation-to-failure for assemblies used for lumbar arthrodesis, starting from the analysis of their structure/geometry, the load applied and the kind of failure when several occur. An AFT model is proposed to model the joint effects of the applied load and the structural dimensions of the brand (namely length and diameter of the screw, presence of a connector or not) on the failure time due to a screw failure. The estimations of S–N curves and maximum permissible load (named critical load) values are provided as functions of the structural dimensions of the product. This allows comparisons of devices in terms of key factors determining product behavior and ageing under loading stress.     

Differences in drinking expectancies and motives for regular education and special education high school students with emotional/behavioral disorders

Alcohol expectancies and drinking motives were compared for regular education students (n=159) and students with emotional/behavioral disorders (EBD) receiving special education services (n=51). Differences existed between groups with respect to expected negative social consequences and emotional and physical outcomes associated with drinking. Across groups, drinkers reported more positive alcohol expectancies than non-drinkers, while non-drinkers reported more negative alcohol expectancies than drinkers. Differences also existed between the regular education and EBD students who drank with respect to coping, conformity, and social motives. Accounting for sample sizes differences, the relationship between alcohol use and negative physical effect was stronger for regular education students, while the relationship between alcohol use and conformity motives was stronger for the EBD group.     

Sexual Orientation and Wage Discrimination in France: The Hidden Side of the Rainbow

This article is the first study to present an econometric evaluation of wage discrimination based on sexual orientation in the French labor market. Having identified same-sex couples using the French Employment Survey, we estimate the wage gap related to sexual orientation in the private and public sectors, in order to analyze whether or not lesbians and gays suffer a wage penalty. The results obtained show the existence of a wage penalty for homosexual male workers, as compared with their heterosexual counterparts, in both the private and public sectors; the magnitude of this discrimination varies from about ?6.5?% in the private sector, to ?5.5?% in the public sector. In the private sector, the wage penalty suffered by gay employees is higher for skilled workers than for the unskilled, and??in both sectors??the wage penalty is higher for older workers than for younger ones. As with many other countries, we do not find any evidence of the existence of a wage discrimination against lesbians.     

Combining Quantitative Risk Assessment of Human Health,Food Waste,and Energy Consumption: The Next Step in the Development of the Food Cold Chain?

The preservation of perishable food via refrigeration in the supply chain is essential to extend shelf life and provide consumers with safe food. However, electricity consumed in refrigeration processes has an economical and an environmental impact. This study focuses on the cold chain of cooked ham, including transport, cold room in supermarket, display cabinet, transport by consumer, and domestic refrigerator, and aims to predict the risk for human health associated with Listeria monocytogenes, the amount of food wasted due to the growth of spoilage bacteria, and the electrical consumption to maintain product temperature through the cold chain. A set of eight intervention actions were tested to evaluate their impact on the three criteria. Results show that the modification of the thermostat of the domestic refrigerator has a high impact on food safety and food waste and a limited impact on the electrical consumption. Inversely, the modification of the airflow rate in the display cabinet has a high impact on electrical consumption and a limited impact on food safety and food waste. A cost–benefit analysis approach and two multicriteria decision analysis methods were used to rank the intervention actions. These three methodologies show that setting the thermostat of the domestic refrigerator to 4 °C presents the best compromise between the three criteria. The impact of decisionmaker preferences (criteria weight) and limitations of these three approaches are discussed. The approaches proposed by this study may be useful in decision making to evaluate global impact of intervention actions in issues involving conflicting outputs.     

Dealing with the wicked issue of child poverty: Inter-organizational networks as forums for collective debate and reflection

In the international realm, inter-organizational networking is perceived as a highly relevant instrument in social policy that enables welfare organizations to deal with “wicked issues.” In this article, we discuss the central empirical findings acquired from a recent qualitative research project that focuses on inter-organizational networks that were formed at the local level to deal with the wicked issue of child poverty as a complex and multidimensional social problem. We explore how the network discussions about normative value orientations in four inter-organizational networks evolve, and identify three central fields of tension that illustrate the complexity for local welfare actors in and across networks to create network strategies in dealing with child poverty: (a) selective versus universal provision, (b) conditional versus unconditional strategies, and (c) instrumental versus lifeworld-oriented approaches. Our findings show that networks can function as valuable forums for collective debate and reflection, since different approaches and perspectives to tackle the problem of child poverty can be confronted with each other. Creating such a forum has the potential to challenge dominant conceptualizations and undesirable assumptions of complex social problems that are present in welfare practices and policies.     

Pathological Gamblers: Inpatients’ versus Outpatients’ Characteristics

Several researchers and clinicians have questioned the advantages and disadvantages of inpatient and outpatient treatment for people suffering from pathological gambling. This study compares the characteristics of pathological gamblers seeking inpatient and outpatient treatment. A total of 233 pathological gamblers (inpatients = 134, outpatients = 99) participated in the study. Results show that inpatients have more severe gambling problems than those receiving outpatient services. Similar results were obtained on most other related variables such as anxiety, depression, alcohol consumption, and comorbidity. These results are discussed in terms of the costs and benefits of these two treatment modalities.     

Plural forms versus franchise and company-owned systems: A DEA approach of hotel chain performance

Plural form tends to be the most popular organization form in retail and service networks compared to purely franchised or purely company-owned systems. In the first part, this paper exposes the evolution of researchers’ state of mind from the way of thinking which considers franchising and ownership as substitutable organizational forms to theories which analyze the utilization of both franchise and company arrangements. The paper describes the main attempts to explain theoretically the superiority of plural forms. In the second part, the paper discusses the hypothesis which says that there is a relationship between the organizational form of the chain and its efficiency score. It is demonstrated through the application of a data envelopment analysis method on French hotel chains that plural form networks are in average more efficient than strictly franchised and wholly owned chains. The Kruskal–Wallis test which is a distribution-free rank-order statistic is used to statistically verify this relationship. The result does not permit the rejection of the null hypothesis regarding whether an organizational form is more efficient than another one. Hence, this paper opens prospects for researches aiming at testing the organizational form effect on different samples and with other methods.     

Avec tact et mesure ? Les médecins généralistes français aux prises avec les évaluations chiffrées de leur pratique

The article focuses on the effects of statistically evaluating the quality of practice in general medicine. Putting the reforms that have affected the private practice of medicine in France in perspective shows that the gradual deployment of ways of governing it has recently taken a decisive metrological turn. We envision the impact on GPs through two original studies devoted to preventive care. Criticism and professional forms of resistance are examined before delving into the experience and arguments of practitioners who consent to the idea of measuring medical work, or even agree to do it themselves, in order to assess the current inflections of the professional model as well as of the organization of medicine in the private sector.     

With tact and measure? French doctors wrestling with the idea of assessing their medical practice

This article focuses on the impact of measuring quality in family medicine. Throwing the reforms that have affected private practice into temporal perspective shows that it has recently undergone a decisive “metric-oriented turn”. Effects of quantitative assessment on general practitioners are observed thanks to two original studies on preventive care. Professionals’ critiques and forms of resistance are examined before delving into the experiences and arguments of GPs who consent to the measurement of medical work, even agreeing to do it themselves. We end by evaluating the ongoing inflections of the professional model and the way the private medical sector in France is governed.     

Parametric inference in a perturbed gamma degradation process

Abstract

We consider a degradation model which is the sum of two independent processes: an homogeneous gamma process and a Brownian motion. This model is called perturbed gamma process. Based on independent copies of the perturbed gamma process observed at irregular instants we propose to estimate the unknown parameters of the model using the moment method. Some general conditions allow to derive the asymptotic behavior of the estimators. We also show that these general conditions are fulfilled for some specific observation schemes. Finally, we illustrate our method by a numerical study and an application to a real data set.