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51.
This paper analyzes the cost increases due to demand uncertainty in single-level MRP lot sizing on a rolling horizon. It is shown that forecast errors have a tremendous effect on the cost effectiveness of lot-sizing techniques even when these forecast errors are small. Moreover, the cost differences between different techniques become rather insignificant in the presence of forecast errors. Since most industrial firms face demand uncertainty to some extent, our findings may have important managerial implications. Various simulation experiments give insight into both the nature and the magnitude of the cost increases for different heuristics. Analytical results are developed for the constant-demand case with random noise and forecasting by exponential smoothing. It is also shown how optimal buffers can be obtained by use of a simple model. Although the analysis in this paper is restricted to simplified cases, the results merit further consideration and study. This paper is one of the first to inject forecast errors into MRP lot-sizing research. As such it attempts to deal with one of the major objections against the practical relevance of previous research in this area.  相似文献   
52.
Alter G  Dribe M  Van Poppel F 《Demography》2007,44(4):785-806
Researchers from a number of disciplines have offered competing theories about the effects oJ childbearing on parents 'postreproductive longevity. The "disposable soma theory" argues that investments in somatic maintenance increase longevity but reduce childbearing. "Maternal depletion" models suggest that the rigors of childrearing increase mortality in later years. Other researchers consider continued childbearing a sign of healthy aging and a predictor of future longevity. Empirical studies have produced inconsistent and contradictory results. Our focus is on the experience of widowhood, which has been ignored in previous studies. We hypothesize that the death of a spouse is a stressful event with long-term consequences for health, especially for women with small children. Data are drawn from historical sources in Sweden, Belgium, and the Netherlands from 1766 to 1980. Postreproductive mortality was highest among young widows with larger families in all three samples. Age at last birth had little or no effect. We conclude that raising children under adverse circumstances can have long-lasting, harmful effects on a mother's health.  相似文献   
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Entering the work of world can involve significant challenges for the beginning practitioner. The transition process from university to work can play an important role in the emerging practitioner’s development as a social worker. The present longitudinal study follows 12 Swedish social work graduates from university and over their first four years in practice. The study provides an insight into how newly educated practitioners may experience the transition from university to the world of work and considers how they can be prepared and supported to meet the challenges of practice within contemporary work contexts. The students were first interviewed just prior to leaving university [see Tham &; Lynch (2014). Prepared for practice? Graduating social work students’ reflections on their education, competence and skills. Social Work Education, 33(6), 704–717]. This paper captures the reflections of these students after four months in practice. Feelings of unpreparedness, unorganised, or even ‘chaotic’ perceptions of the workplace and uncertainty about the future were emergent themes, particularly among new practitioners employed in social services. The findings illustrate the vulnerability of these new practitioners and the importance of workplace induction and the provision of adequate support in their new professional roles.  相似文献   
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Objective: To examine differences in complete response rates for depression screening questions based on demographic characteristics. Methods: Cross-sectional study examining associations between demographic characteristics and completely responding depression-screening questions. Participants: “Healthy Minds Study” data, collected in a public University in February 2016, where 7,326 students participated. Results: women (AOR: 0.69; 95% CI =0.57–0.83) and gay/lesbian students (AOR: 0.24; 95% CI =0.10–0.60) had better complete response rates. Non-US (AOR: 1.46; 95% CI =1.03–2.07), black (AOR: 3.32; 95% CI =1.92–5.77), and Middle-Eastern students (AOR: 3.73; 95% CI =1.73–8.02) had lower complete response rates. Conclusions: Our study shows sex, gender, citizenship, and race categories have significant differences in complete response rates for the outcome. Our findings have several implications; including recognizing interventions for depression based on responders may not target those that tend to be “partial-responders”. Efforts in survey design, recruiting and completion of surveys should be maximized.  相似文献   
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When parents divorce, grandparents can play a supportive role in the lives of their grandchildren, but a parental divorce may also put grandchild–grandparent ties under pressure. In this study the authors investigated how grandchildren of married and divorced parents differ in the frequency of face‐to‐face contacts with grandparents and how this is mediated by postdivorce residence arrangements. Based on the multi‐actor survey “Divorce in Flanders,” they used reports of contact provided by more than 1,000 grandchildren and compared them with more than 1,100 grandparent reports for validation. The results showed that grandchildren from divorced parents have fewer contacts with their grandparents than grandchildren whose parents are married but that it is the postdivorce residence arrangement of grandchildren that produces this result. When grandchildren live with their divorced father or in a shared residence arrangement, they even see paternal grandparents more often than grandchildren with married parents.  相似文献   
58.
This article examines individual variability in sexual desire and sexual satisfaction by exploring the relation between these sexual aspects and sexual attitudes (implicit and explicit) and by taking gender into account, as this has been shown to be an influential factor. A total of 28 men and 33 women living in heterosexual relationships completed questionnaires assessing sexual desire (dyadic, solitary), sexual satisfaction, and explicit sexual attitudes. An adapted version of the Affect Misattribution Procedure was used to assess implicit sexual attitudes. Results showed higher levels of dyadic and solitary sexual desire in men than in women. No gender differences were found regarding sexual satisfaction or sexual attitudes. High dyadic sexual desire was associated with positive implicit and explicit sexual attitudes, regardless of gender. However, solitary sexual desire was significantly higher in men than women and was associated, in women only, with positive implicit sexual attitudes, suggesting that solitary sexual desire may fulfill different functions in men and women. Finally, sexual satisfaction depended on the combination of explicit and implicit sexual attitudes in both men and women. This study highlights the importance of considering both implicit and explicit sexual attitudes to better understand the mechanisms underlying individual variability in sexual desire and satisfaction.  相似文献   
59.
Adding to the debate on the integrative or marginalizing nature of female part-time work, this article provides a comparative analysis of the implications of female part-time work for different intrinsic job quality dimensions and job satisfaction. Drawing on national micro-data from Britain, Germany, the Netherlands, and Sweden, our multivariate analyses show cross-national similarities in terms of lower job learning opportunities for female part-timers. We found a significantly higher incidence of repetitiveness only among Swedish female part-timers and lower degrees of task discretion among British, Dutch, and Swedish women working part-time hours. Female part-timers were either equally satisfied with their work as female full-timers or even more satisfied. This held true also after accounting for the lower intrinsic job quality of part-time work. While women working part-time hours were as affected by their job quality characteristics as were full-timers, we conclude that the shorter hours of work per se provide an important additional source of job satisfaction.  相似文献   
60.
In order to assess the accuracy of the figures reported in NPOs’ financial statements, I perform a digital analysis on Belgian non-profit organizations’ financial statements for accounting years 2007 up to 2012. Specifically, I compare observed frequencies for digits in the second-from-the-left position with expected frequencies based on Benford’s Law. Results based on the full sample indicate that observed frequencies strongly conform to Benford’s Law (and thus suggest a high degree of accuracy of the figures reported in NPOs’ financial statements). Nevertheless, I note statistically significant deviations from Benford’s Law (both for the entire distribution and at the individual digit level). The largest deviation is noted for zeroes in the second position (i.e., a significantly positive deviation), which can be explained based on humans’ reliance upon so-called cognitive reference points. Considering different sub-samples, I note that observed deviations from Benford’s Law are largest for the smallest non-profits and those non-profits that rely most heavily on grants and/or donations.  相似文献   
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