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271.
Correlation of long-term temperature variability and population density was investigated in an isolated mountain environment case study for the sixteenth to eighteenth centuries period. Andorra (Central Pyrenees) was chosen as a case study location due to its harsh environmental conditions and to its historical politically neutral position. Reconstructed temperatures for the eighteenth century, based on dendrochronological data, show strong statistical correlations with death inventories (rs = ?0.359, p < 0.001), reflecting an increase in mortality at lower temperatures. These conclusions were extended to the sixteenth and seventeenth centuries, using volcanic activity data in order to compensate for a scarcity of dendrochronological data covering this period. Indirect temperature effects related to vegetation growth and crop yield have also been found. Therefore, this study demonstrates the historical influence of climate change on population density in harsh mountain areas.  相似文献   
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This article focuses on the location, time, and spatio-temporal components associated with suitably aggregated data to improve prediction of individual asset values. Such effects are introduced in the context of hierarchical models, which we find more natural than attempting to model covariance structure. Indeed, our cross-sectional database, a sample of 7,936 transactions for 49 subdivisions over a 10-year period in Baton Rouge, Louisiana, precludes covariance modeling. A wide range of models arises, each fitted using sampling-based methods because likelihood-based fitting may not be possible. Choosing among an array of nonnested models is carried out using a posterior predictive criterion. In addition, one year of data is held out for model validation. A thorough analysis of the data incorporating all of the aforementioned issues is presented.  相似文献   
274.
We derive and numerically evaluate the bias and mean square error of the inequality constrained least squares estimator in a model with two inequality constraints and multivariate terror terms. Our results suggest that qualitatively, the estimator properties found for models with normal errors carry over to the case of multivariate terrors.  相似文献   
275.
In May 2012, the Committee of Health and Medicinal Products issued a concept paper on the need to review the points to consider document on multiplicity issues in clinical trials. In preparation for the release of the updated guidance document, Statisticians in the Pharmaceutical Industry held a one‐day expert group meeting in January 2013. Topics debated included multiplicity and the drug development process, the usefulness and limitations of newly developed strategies to deal with multiplicity, multiplicity issues arising from interim decisions and multiregional development, and the need for simultaneous confidence intervals (CIs) corresponding to multiple test procedures. A clear message from the meeting was that multiplicity adjustments need to be considered when the intention is to make a formal statement about efficacy or safety based on hypothesis tests. Statisticians have a key role when designing studies to assess what adjustment really means in the context of the research being conducted. More thought during the planning phase needs to be given to multiplicity adjustments for secondary endpoints given these are increasing in importance in differentiating products in the market place. No consensus was reached on the role of simultaneous CIs in the context of superiority trials. It was argued that unadjusted intervals should be employed as the primary purpose of the intervals is estimation, while the purpose of hypothesis testing is to formally establish an effect. The opposing view was that CIs should correspond to the test decision whenever possible. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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Under what circumstances do close allies sacrifice their unity? By what process do bonds break? Although it might be argued that political ruptures are determined by incommensurable ideas (policies, philosophies) or by contentious personalities (temperament, character), we argue that neither explanation is sociologically sufficient. Extending the theories of interpersonal ruptures of Diane Vaughan and Robert Emerson to political domains, we take a relational approach to politics by emphasizing the centrality of the availability of reputational information, networks of supporters, and public displays of antagonism in response to affronts within systems of institutional power. Our approach to public ruptures draws on a detailed case study: the broken alliance between presidents Theodore Roosevelt and William Howard Taft, a dramatic instance of changing master-protégé relationship. The transition from close interpersonal alliance to public distaste typically involves four stages that expand a relational breach to an irreparable rupture: (1) personal grievance, (2) substantive disagreement, (3) public awareness, and (4) network activity. While every detailed case has limits, we note comparable instances and contend that this model applies broadly to broken partnerships in politics or other public domains.  相似文献   
278.
Review of Economics of the Household - Using two-year panel data from the Medical Expenditure Panel Survey (MEPS) for 2004 to 2012, we examine how the intra-family allocation of health care...  相似文献   
279.
NGOs that operate as part of transnational advocacy networks face a number of ‘legitimacy challenges’ concerning their rights to participate in the shaping of global governance. Outlining the legitimacy claims that development NGOs make, the article argues that ‘legitimacy’ is a socially constructed quality that may be ascribed to an NGO by actors and stakeholders with different viewpoints. NGOs operating transnationally link disparate communities and conceptions of legitimacy, and undermine the discourse and practice of sovereignty. Therefore such NGOs will find it difficult to be universally regarded as legitimate, especially by states that hold a sovereignty‐based conception of legitimacy. However, relationships are the building blocks of networks, and efforts to improve them should not be abandoned simply because ‘legitimacy’ is too closely connected with sovereignty. In particular, NGOs ought to improve their relationships with the poor and marginalized communities whose interests they claim to promote. To this end, the concept of ‘political responsibility’ is suggested as a pragmatic approach to understanding power relations as they arise in transnational advocacy networks and campaigns.  相似文献   
280.
We evaluated the use of a clicker sound as a conditioned reinforcer to teach behavior interventionists appropriate clinical skills during in-situ training. A multiple-baseline-across-behaviors design indicated that the intervention was effective in increasing all target behaviors for all participants. For two of the participants, we conducted maintenance probes one to five weeks after the final training session and performance continued to occur at a high level. Although the participants ranked the contingent clicker presentation as less disruptive and more fair than typical feedback methods, they ranked it as slightly less helpful, less worthwhile, and less pleasant than typical feedback methods. These findings suggest that clicker training can play a valuable role in training mental health professionals.  相似文献   
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