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161.
Zedan SH 《New directions for youth development》2007,(116):87-98, 11
Because of poverty, many girls and young women throughout Egypt neglect their education in order to marry early, help in the fields, gain immediate employment, or carry out domestic labor to meet family needs. In Egypt, the Academy for Educational Development's Community YouthMapping (CYM) has been structured to provide a solid foundation for a systemic approach to education reform. CYM focuses on changing communities' perceptions and behavior through its youth and mechanisms to develop transferable skills to those who have traditionally been marginalized during afterschool time. 相似文献
162.
Ovarian cancer is the leading cause of gynaecological cancer death. The mortality rate of ovarian cancer could be greatly decreased if there were a screening test which was able to detect the disease at an early stage, resulting in an increased probability of cure. The most promising prospect for the early detection of ovarian cancer comes from the rapidly advancing field of clinical proteomics. An increasing number of reports on the potential clinical application of proteomics research for early detection as well as risk assessment and management of ovarian cancer are being published. Although the research is very promising, major technical challenges are still preventing new discoveries in ovarian cancer proteomics from being translated into clinical practice. 相似文献
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164.
In recent years, a variety of regression models, including zero-inflated and hurdle versions, have been proposed to explain the case of a dependent variable with respect to exogenous covariates. Apart from the classical Poisson, negative binomial and generalised Poisson distributions, many proposals have appeared in the statistical literature, perhaps in response to the new possibilities offered by advanced software that now enables researchers to implement numerous special functions in a relatively simple way. However, we believe that a significant research gap remains, since very little attention has been paid to the quasi-binomial distribution, which was first proposed over fifty years ago. We believe this distribution might constitute a valid alternative to existing regression models, in situations in which the variable has bounded support. Therefore, in this paper we present a zero-inflated regression model based on the quasi-binomial distribution, taking into account the moments and maximum likelihood estimators, and perform a score test to compare the zero-inflated quasi-binomial distribution with the zero-inflated binomial distribution, and the zero-inflated model with the homogeneous model (the model in which covariates are not considered). This analysis is illustrated with two data sets that are well known in the statistical literature and which contain a large number of zeros. 相似文献
165.
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167.
Nancy H. Hornberger 《Journal of population economics》2006,19(4):879-883
Acknowledgments
Acknowledgement to editorial collaborators 相似文献168.
We examine the phenomenon of shifting production bottlenecks from an analytic perspective. We quantify the propensity of a work center to be a bottleneck, defined as maximal queue length, using a simple Jackson production network model. Comparison of the analytic model against an empirical simulation-based model shows that the two are in good agreement. A scalar measure of bottleneck shiftiness is proposed and used to investigate several policies for mitigating shiftiness. Simulation experiments show that several commonly observed managerial policies for coping with shifting bottlenecks actually increase shiftiness, but that shiftiness declines when the capacity of nonbottleneck resources is increased. 相似文献
169.
The present study examined the career advancement prospects of MIS and non-MIS employees, as well as the relationships of career advancement prospects with job performance evaluations, job satisfaction, career satisfaction, and organizational commitment for MIS and non-MIS professionals and managers. Participants included 134 MIS professionals and managers and 397 non-MIS professionals and managers of a large communications company. The results provided no evidence that MIS employees experience more restricted career advancement prospects than non-MIS employees. In addition, job performance evaluations generally had positive effects on career advancement prospects; career advancement prospects had a number of positive effects on job satisfaction, career satisfaction, and organizational commitment; and job satisfaction and career satisfaction had positive effects on organizational commitment. These findings are related to prior research, suggestions for future research are offered, and implications for the management of MIS employees are identified. 相似文献
170.
Kee H. Chung 《决策科学》1993,24(6):1215-1221
This paper presents a contingent-claims approach to project valuation when capital expenditures are made sequentially over time. It focuses on an important facet of sequential investment projects that the firm can undertake—or pass up projects—as more information becomes available. The contingent-claims approach takes account of this important feature of firms' investment decision process, whereas the traditional capital budgeting procedure does not. Since the traditional method does not reflect the options nature of investment opportunities, it underestimates the value of sequential investment projects. As a result, a naive implementation of the traditional capital budgeting procedure could result in rejecting profitable projects. The extent of undervaluation associated with the traditional capital budgeting procedure is greater when the correlation between the random component of the future asset value and that of the required capital expenditure is smaller and/or when the growth rate of the required capital expenditure is higher. 相似文献