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1.
Social Indicators Research - Debates about the appropriate role of markets and governments are often shaped by sharply contrasting opinions. Based on individual data from the World Values Survey...  相似文献   
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For large cohort studies with rare outcomes, the nested case-control design only requires data collection of small subsets of the individuals at risk. These are typically randomly sampled at the observed event times and a weighted, stratified analysis takes over the role of the full cohort analysis. Motivated by observational studies on the impact of hospital-acquired infection on hospital stay outcome, we are interested in situations, where not necessarily the outcome is rare, but time-dependent exposure such as the occurrence of an adverse event or disease progression is. Using the counting process formulation of general nested case-control designs, we propose three sampling schemes where not all commonly observed outcomes need to be included in the analysis. Rather, inclusion probabilities may be time-dependent and may even depend on the past sampling and exposure history. A bootstrap analysis of a full cohort data set from hospital epidemiology allows us to investigate the practical utility of the proposed sampling schemes in comparison to a full cohort analysis and a too simple application of the nested case-control design, if the outcome is not rare.

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在零售4.0时代,渠道的多样化不仅丰富了数据源,还能迅速生成大量数据,需要通过分析大数据,为决策提取有意义的信息,通过分析先行发货的重要性,提出了一种基于遗传算法(GA)的优化模型,预测顾客何时购买,然后在顾客线下单前将产品运送到距顾客最近的配送中心,解决先行发货中存在的问题。研究认为,需要先部署云计算来存储所有渠道生成的大数据,再应用基于集群的关联规则挖掘研究顾客的购买行为,根据“如果-那么”预测规则预测未来的采购情况,最后利用修正的遗传算法生成最优的先行发货计划;这种遗传算法考虑了其在运输成本和运输距离之外,还有预测规则的置信度,利用大量的数值实验权衡了先行发货中的不同因素,验证了模型的最优可靠性  相似文献   
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This paper reviews economic policies and instruments available to the developed countries to reduce unwanted migration from developing countries, not all of which is irregular migration. Countries generally welcome legal immigrants and visitors, try to make it unnecessary for people to become refugees and asylum seekers, and try to discourage, detect, and remove irregular foreigners. There are three major themes: 1. There are as many reasons for migration as there are migrants, and the distinction between migrants motivated by economic and non–economic considerations is often blurred. Perhaps the best analogy is to a river – what begins as one channel that can be managed with a dam can become a series of rivulets forming a delta, making migration far more difficult to manage. 2. The keys to reducing unwanted migration lie mostly in emigration countries, but trade and investment fostered by immigration countries can accelerate economic and job growth in both emigration and immigration countries, and make trading in goods a substitute for economically motivated migration. Trade and economic integration had the effect of slowing emigration from Europe to the Americas, between southern Europe and northern Europe, and in Asian Tiger countries such as South Korea and Malaysia. However, the process of moving toward freer trade and economic integration can also increase migration in the short term, producing a migration hump, and requiring cooperation between emigration and immigration destinations so that the threat of more migration does not slow economic integration and growth. 3. Aid, intervention, and remittances can help reduce unwanted migration, but experience shows that there are no assurances that such aid, intervention, and remittances would, in fact, lead migrants to stay at home. The better use of remittances to promote development, which at US$65 billion in 1999 exceeded the US$56 billion in official development assistance (ODA), is a promising area for cooperation between migrants and their areas of origin, as well as emigration and immigration countries. There are two ways that differences between countries can be narrowed: migration alone in a world without free trade, or migration and trade in an open economy. Migration will eventually diminish in both cases, but there is an important difference between reducing migration pressures in a closed or open world economy. In a closed economy, economic differences can narrow as wages fall in the immigration country, a sure recipe for an anti–immigrant backlash. By contrast, in an open economy, economic differences can be narrowed as wages rise faster in the emigration country. Areas for additional research and exploration of policy options include: (1) how to phase in freer trade, investment, and economic integration to minimize unwanted migration; (2) strategies to increase the job–creating impacts of remittances, perhaps by using aid to match remittances that are invested in job–creating ways.  相似文献   
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Several Cooperative Efforts to Manage Emigration (CEME) members visited the Federal Republic of Yugoslavia (FRY) in early June 2001 to examine the new Government's approach to migration issues. We found that both the Federal Government and the Serb Republic are faced with three principal issues related to immigration and refugees that require substantial cooperation with North American and European countries that are donors of international aid, as well as recipients of Yugoslav migrants and third country nationals transiting the FRY.
First, they are faced with migration issues that the international community considers priorities, including demilitarizing border management; combating human smuggling and trafficking; and drafting and implementing an aliens law, which includes asylum policies and procedures consistent with international standards.
Second, they need to plan for the return or integration of 350,000 refugees from Croatia and Bosnia, and another 150,000 internally displaced Yugoslavs from Kosovo, primarily by offering dual citizenship in the FRY, and Croatia and Bosnia so refugees can integrate in the FRY, but retain rights and privileges according to Croatians or Bosnians.
Third, it is important to build bridges to Yugoslavs abroad in order to attract remittances and the return of the professionals needed to rebuild the FRY.  相似文献   
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Adolescents' and mothers' understanding of children's self‐determination and nurturance rights was examined in the context of the home. In individual interviews, 141 sixth, eighth, and tenth graders and their mothers responded to hypothetical vignettes in which a child story character wished to exercise a right that conflicted with parental practices. For each vignette, participants were asked to judge whether the story character should have the right in question and to provide a justification for their decision. Generally, eighth and tenth graders were more likely than their mothers to endorse requests for self‐determination and less likely than their mothers to support requests for nurturance. Mothers of tenth graders were more likely to support requests for self‐determination and less likely to favor adolescents' request for nurturance in the home than were mothers of sixth and eighth graders. In terms of reasoning, adolescents and mothers were more likely to consider the individuals' rights when discussing self‐determination situations, whereas nurturance situations elicited responses pertaining to participants' understanding of familial roles and relationships. Furthermore, mothers' reasoning about childrenà s rights reflected sensitivity to the developmental level of their children. The findings are discussed in terms of previous research on the development of children's understanding of rights and adolescent autonomy.  相似文献   
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省略的语用条件和语用策略   总被引:1,自引:0,他引:1       下载免费PDF全文
日语会话句式后半部分的省略现象可运用格赖斯的合作原则(Cooperative Principle,简称CP)和利奇的礼貌原则(Politeness Principle,简称PP)来进行诠释,它是人际交流的一种语用策略,但同时需具备语用条件.语言知识语境因素是它的语用条件之一.  相似文献   
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新闻报道策划 在近几年的新闻实践中应用非常广泛。就报道主题、整合信息、沟通受众和发挥媒体整体优 势等方面论述了新闻报道策划的实践意义。  相似文献   
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