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171.
In this paper, we investigate the relationship between a functional random covariable and a scalar response which is subject to left-truncation by another random variable. Precisely, we use the mean squared relative error as a loss function to construct a nonparametric estimator of the regression operator of these functional truncated data. Under some standard assumptions in functional data analysis, we establish the almost sure consistency, with rates, of the constructed estimator as well as its asymptotic normality. Then, a simulation study, on finite-sized samples, was carried out in order to show the efficiency of our estimation procedure and to highlight its superiority over the classical kernel estimation, for different levels of simulated truncated data.  相似文献   
172.
The authors used a standardized questionnaire to survey 201 international and 193 German students at the University of Bielefeld, Germany, to determine differences in health practices between the 2 groups and to identify targets for health-promoting interventions. Multivariate logistic regression models revealed that long-term female international students (those whose duration of residency in Germany was more than 2 years) had lower levels of physical activity and alcohol consumption than their German counterparts and higher rates of smoking independently associated with international citizenship. Short-term international female students were less likely than German students to receive social support. Among men, long-term international student status was associated with daily smoking and inconsistent seat belt use, whereas short-term student status was associated with a lower rate of seat belt use, a higher level of perceived stress, and a healthier diet, compared with domestic students. Findings from the study could give rise to health-promotion activities for international students at German universities; additional studies at other European universities are necessary before making further recommendations.  相似文献   
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A questionnaire investigating adolescents' opinions and experiences regarding marijuana use was administered to 163 adolescents and young adults (96 boys and 67 girls) aged 13 to 20 (mean age = 16.8, s.d. = 1.5). Items referred to marijuana and other substances' dangerousness, representations regarding the positive and negative consequences of marijuana use. Responses were compared according to marijuana use status (classified into never/occasional use, current regular use and past regular use). Results show that adolescents' opinions differ according to their experience with marijuana use. Current regular users evaluate marijuana as less dangerous, but alcohol and heroin as more dangerous in comparison with never/occasional and past users. Current and past users are more likely to define marijuana as a medical drug and a plant used in agriculture, and less likely to define it as an illegal drug. Current and past users evaluate marijuana use as a way to cope with stress, to relax to a greater extent than do never/occasional users do. The latter attribute more negative consequences to marijuana use such as diminished driving ability and school performance and a pathway to hard drugs.  相似文献   
175.
The analysis of labour supply involves two issues: whether individuals participate in the labour market and, if they do, for how many hours. In this article we investigate the differences in labour supply of married women and cohabiting women in the Netherlands; we try to answer the question how these differences can be explained. From this study, it can be concluded that differences between both categories of women in participation and in weekly hours worked can predominantly be explained by differences in characteristics (e.g. age, net wage rate, and age of children), than by differences in behaviour. The empirical results indicate that cohabiting women are more economically independent than married women. However for married women we found evidence that there was increased economic independence during the eighties; i.e. their weekly hours work has become less affected by the income of their partners.  相似文献   
176.
This article presents a methodology based on two complementary approaches, thus allowing a selection of maximal concentration in foodstuffs for determining appropriate countermeasures. The first approach is based on a minimal and maximal per capita intervention level and takes into account the annual intake of each product. The second one is based on a cost-benefit analysis, comparing the advantages of a countermeasure concerning those products presenting a contamination higher than a given maximal concentration (in terms of reduction of cost of the detriment associated with the risk), with its drawbacks (in terms of cost of the products) in order to select the "ALARA" maximal concentration. This second approach is used as a complement to the first one. The results obtained through these two approaches are given for four products (milk, meat, fresh vegetables, and corn) and two nuclides (Cs-137 and I-131). These are presented for various scenarios: one or various products contaminated by one or various radionuclides. It is concluded that these two approaches are complementary, the first one being related to individual risk and the second to collective risk. Therefore, these approaches are both of interest in the context of the elaboration of modalities for the radiological control of foodstuffs following an accidental release and both methods may be useful for determining appropriate countermeasures.  相似文献   
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178.
This study evaluates attitudes and knowledge of parents regarding gambling behaviors among youths, aged 5 to 17 years. Telephone interviews were conducted among 279 randomly selected parents (32% fathers and 68% mothers) in the Quebec City region. Results indicate that parents overestimate the age of children's first wagers and underestimate the probability that their own child has already gambled. Most parents (86%) believe that the availability of gambling for youths should be reduced and that schools should include prevention programs concerning problem gambling. Results also show that parents fail to associate excessive gambling with poor grades or with alcohol and drug use. Finally, 84% of the parents reported that they would accept buying lottery tickets for their child. These results suggest that prevention programs for excessive gambling among children should include information for parents.  相似文献   
179.
According to prior literature, risk determines the international strategies firms adopt, together with cultural and geographical distance. However, the effect of distance, whether cultural or geographical, remains insufficiently tested and seemingly contradictory. To investigate the potential determinants of international firm strategies, this study draws a sample of 759 Japanese subsidiaries worldwide. Statistical analyses confirm the ambiguous effect of distance (cultural and geographical) on internationalization strategies, especially compared with the effect of risk.  相似文献   
180.
ABSTRACT: In this article the hypothesis that a higher level of subsidized day-care facilities leads to an increase in female labour supply is tested for the Netherlands on the basis of two surveys. The results show that (allowing for the women's wage rate, her non-labour income, her age, and the presence of children) labour supply is higher when subsidized day-care supply is higher. However, after including variables that reflect social norms the effect of day-care supply on female labour supply, though still positive and significant, becomes much weaker.  相似文献   
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