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11.

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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Journal of Population Research - This paper details efforts to link administrative records from the Internal Revenue Service (IRS) to American Community Survey (ACS) and 2010 Census microdata for...  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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In this paper, we are studying social identities within a cross-national framework as they are reflected in values regarding social institutions. We compare value items to infer similarities and differences between Japan and the US, but more importantly we analyze value configurations, using factor analysis, as an expression of underlying cultural expectations. We also argue that the way values are transmitted further defines the distinctive cultural basis of social identities. Using a unique data set, The Generations Survey , we propose to contribute theoretically and methodologically to understanding the role of culture in postmodern societies. Our research, based on identical national surveys collected in 1995, provides a systematic way to compare values in two countries. The research builds on and specifies existing ethnographic case studies and in-depth interviews around a variety of themes that shape social identities such as the link between family and work expectations, the role of ethical values in business, the importance of national identification, and the meaning of community involvement. The paper concludes by suggesting that despite homogenizing trends and surface similarities, cultural distinctiveness persists in the ways values cluster and is transmitted in the family, shaping the social identities of Japanese and US respondents.  相似文献   
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What do voters really know about party platforms and how do they perceive the contents? Are there any relationships between party election platforms and electoral behavior? Despite of much research on parties, there are hardly any answers to these questions. If political parties devise programmes in order to influence political attitudes or electoral behavior, it will be necessary that these programmes are read by people. But it seems to be unclear if and how people do so. This article shows clearly that voters don’t know much about party manifestoes. Still, programmes are more important for voters than many people believe. Programmes are also an important factor for electoral behavior. But there is still a lack of data to get evident results.  相似文献   
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Institutional Constraints and Deforestation: An Application to Mexico   总被引:1,自引:0,他引:1  
Following North (1990), this article hypothesizes that effective rural institutions may impose additional costs on tropical deforestation through agricultural conversion. This allows a formal agricultural household analysis of institutional constraints on deforestation and therefore a method of empirically testing whether there is any significant difference in the actual level of forest land conversion under institutional constraints compared to the level of conversion under pure open access. A dynamic panel analysis for agricultural planted area in Mexico at state level and over the 1960–85 period confirms that institutional constraints on land clearing affected deforestation during the pre-NAFTA era.  相似文献   
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