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21.
Although one of the most marked demographic trends observed over the twentieth century is the increased rate of divorce, relatively little research has explored the effects of these changing marital patterns in the context of an aging society. Using a sample of lone elderly parents and their adult children, we analyze the direct and indirect effects of marital disruption on four important dimensions of intergenerational transfers: coresidence, financial assistance, adult children's provision of informal care, and parental purchase of paid care. Our findings suggest that divorce has deleterious effects on intergenerational transfers, particularly for elderly fathers. Remarriage further reduces exchange. Our results reveal that parents engage in lower levels of transfers with stepchildren relative to biological children. Moreover, intergenerational transfers are sensitive to characteristics of biological children but not to those of stepchildren. Taken together, these results suggest that exchange at the end of the life course continues to be adversely affected by marital disruption.  相似文献   
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Leaving school prematurely is often claimed to be among the most negative consequences of early marriage and pregnancy for girls in less developed countries. However, an analysis of the relative frequency with which these events actually occur or are named as reasons for leaving school reveals that, at least in the case of francophone Africa, they explain no more than 20 per cent of dropouts. To the extent that demographic events trump school or family factors as determinants of school-leaving, our data indicate that it is union formation--defined by the DHS as first marriage or cohabitation--rather than childbirth that is more likely to have this effect. 'Schoolgirl pregnancy' typically accounts for only between 5 and 10 per cent of girls' departures from school. Furthermore, the risks of leaving school because of pregnancy or marriage have declined over time with the decline in rates of early marriage and childbearing.  相似文献   
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Abstract

The twelfth annual MOBIUS Conference was held June 7–9, 2011, at the Holiday Inn Executive Center in Columbia, Missouri. The MOBIUS consortium of Missouri is currently composed of fifty-nine academic libraries, two public libraries, and the Missouri State Library. The conference offered various opportunities, including a keynote address by Meredith Farkas and a networking dessert session on the first night. The second day featured six concurrent sessions, each having six different presentations, along with delicious food, generous door prizes, and the chance to meet with vendors. The third day consisted of four different four-hour post-conference training sessions. Presentations are available for download from the conference Web site.1  相似文献   
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This article proposes new methodologies for evaluating economic models’ out-of-sample forecasting performance that are robust to the choice of the estimation window size. The methodologies involve evaluating the predictive ability of forecasting models over a wide range of window sizes. The study shows that the tests proposed in the literature may lack the power to detect predictive ability and might be subject to data snooping across different window sizes if used repeatedly. An empirical application shows the usefulness of the methodologies for evaluating exchange rate models’ forecasting ability.  相似文献   
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Barnacle geese ( Branta leucopsis ) make annual migrations between breeding colonies in northern Europe and Eurasia to wintering grounds in Holland. During the migration, they sojourn for several weeks in five areas on the northern coast of Germany. Observers traverse these areas during the course of studying the flocks. Previous belief was that there was little exchange of birds among the five areas; however, some banded birds were observed in more than one area indicating that some movement takes place. In this presentation, we estimate the movement rates among the areas using open- and closed-population models.  相似文献   
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This article considers in-sample prediction and out-of-sample forecasting in regressions with many exogenous predictors. We consider four dimension-reduction devices: principal components, ridge, Landweber Fridman, and partial least squares. We derive rates of convergence for two representative models: an ill-posed model and an approximate factor model. The theory is developed for a large cross-section and a large time-series. As all these methods depend on a tuning parameter to be selected, we also propose data-driven selection methods based on cross-validation and establish their optimality. Monte Carlo simulations and an empirical application to forecasting inflation and output growth in the U.S. show that data-reduction methods outperform conventional methods in several relevant settings, and might effectively guard against instabilities in predictors’ forecasting ability.  相似文献   
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The housing price in Tianjin, one of the typical monocentric cities of China, exhibits a heavily right-tailed distribution even after the logarithm transformation of the price, which might lead to a biased estimation of the parameters under normal distribution assumption. Therefore, the extended Cox proportional hazards regression model and the generalized concept of relative risk are used to identify factors associated with the housing price. The analysis shows that the implementation dates of the macro regulation policies were related to the price changing trends. Qualities of public elementary and secondary schools were significantly associated with the housing price, and the associations between the structure and neighborhood characteristics and the housing price were influenced by the distance of the residential property to downtown Tianjin.KEYWORDS: Cox proportional hazards model, cumulative opportunity method, housing price, restricted cubic splines, relative risk  相似文献   
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