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131.
B.S. Chimni 《International migration (Geneva, Switzerland)》2002,40(5):75-94
A fundamental problem that confronts the European Union today is how it can maintain its commitment to the institution of asylum while checking irregular migration and the abuse of its asylum system. In order to explore a response to this dilemma the paper addresses the following questions: what role can relief and aid policies play in influencing migration patterns? What should be the appropriate approach to the granting of relief and aid to developing countries of first asylum? Should it be viewed as a part of the larger problem of development or be treated as a distinct issue? What kind of a relief/aid model will help refugees return to post–conflict societies and stop the conflict from reproducing itself? The paper examines two different approaches to address these questions: the alliance–containment approach and the distributive–developmental approach. It also looks at some empirical evidence, which reveals that at present it is a conservative alliance–containment approach that informs EU relief and aid practices. This approach, however, does not help achieve the stated objective of checking abuse of asylum and migration procedures while sustaining a commitment to a liberal asylum regime. The paper goes on to identify the gaps in EU policy and the lessons that can be drawn. It concludes by looking at different policy alternatives and suggesting the adoption of a reformist distributive–developmental model. The implementation of this model holds out the hope of reverting to a more liberal asylum regime while controlling irregular migration and “bogus” asylum seekers, for the reformist distributive developmental model takes a more long–term view of migration trends and also seeks to address the growing North–South divide. 相似文献
132.
The small sample performance of least median of squares, reweighted least squares, least squares, least absolute deviations, and three partially adaptive estimators are compared using Monte Carlo simulations. Two data problems are addressed in the paper: (1) data generated from non-normal error distributions and (2) contaminated data. Breakdown plots are used to investigate the sensitivity of partially adaptive estimators to data contamination relative to RLS. One partially adaptive estimator performs especially well when the errors are skewed, while another partially adaptive estimator and RLS perform particularly well when the errors are extremely leptokur-totic. In comparison with RLS, partially adaptive estimators are only moderately effective in resisting data contamination; however, they outperform least squares and least absolute deviation estimators. 相似文献
133.
邵玉铮 《北京林业大学学报(社会科学版)》2003,2(4):73-76
该文依据分类学的原则 ,剖析了沿用一千多年的“永字八法” ,减撇加折 ,构成了“新永字八法”。同时推出了“方圆米格” ,不仅适用于楷书 ,也可传习行、草、隶、篆诸种书体。改进后的“大小多用方圆米格” ,既可写大小多种字体 ,又能提高利用率。 相似文献
134.
B. S. Everitt 《Journal of applied statistics》1994,21(3):63-94
Many methods for obtaining graphical representations of multivariate data have been suggested over the last decade, but it is only relatively recently that software has become available which makes use of these procedures routine. In this paper, a number of examples are used to illustrate the application of graphical methods for the exploration of multivariate data. The diagrams produced may prove useful in consultations with clients and in examining the results from more formal methods. 相似文献
135.
Michael I. Miller Sarang Joshi David R. Maffitt James G. Mcnally Ulf Grenander 《Journal of applied statistics》1994,21(1):141-163
Most real-world shapes and images are characterized by high variability- they are not rigid, like crystals, for example—but they are strongly structured. Therefore, a fundamental task in the understanding and analysis of such image ensembles is the construction of models that incorporate both variability and structure in a mathematically precise way. The global shape models introduced in Grenander's general pattern theory are intended to do this. In this paper, we describe the representation of two-dimensional mitochondria and membranes in electron microscope photographs, and three-dimensional amoebae in optical sectioning microscopy. There are three kinds of variability to all of these patterns, which these representations accommodate. The first is the variability in shape and viewing orientation. For this, the typical structure is represented via linear, circular and spherical templates, with the variability accomodated via the application of transformations applied to the templates. The transformations form groups: scale, rotation and translation. They are locally applied throughout the continuum and of high dimension. The second is the textural variability; the inside and outside of these basic shapes are subject to random variation, as well as sensor noise. For this, statistical sensor models and Markov random field texture models are used to connect the constituent structures of the shapes to the measured data. The third variability type is associated with the fact that each scene is made up of a variable number of shapes; this number is not assumed to be known a priori. Each scene has a variable number of parameters encoding the transformations of the templates appropriate for that scene. For this, a single posterior distribution is defined over the countable union of spaces representing models of varying numbers of shapes. Bayesian inference is performed via computation of the conditional expectation of the parametrically defined shapes under the posterior. These conditional mean estimates are generated using jump-diffusion processes. Results for membranes, mitochondria and amoebae are shown. 相似文献
136.
Sources of drug information among adolescent students 总被引:1,自引:0,他引:1
E Mirzaee P M Kingery B E Pruitt G Heuberger R S Hurley 《Journal of drug education》1991,21(2):95-106
A sample of 1023 eighth and tenth grade students in small to medium-sized central Texas school districts was assessed to determine the amount of information they receive from ten sources about six categories of drugs. The amount of information males reported receiving about each drug category was significantly greater than what females reported, and the amount of information that eighth graders reported receiving about each drug category was significantly greater than what tenth graders reported. Television was the primary source of drug information for all categories of drugs except inhalants, for which friends and television were equally important sources. Parents and printed media (magazines or newspapers) were of secondary importance, followed by friends and teachers. Adolescents were less likely to receive drug-related information from experience, siblings, church, doctors, and police. The reliance on the mass media for drug information in smaller school districts is a pattern which has been previously observed in larger urban districts. This consistency suggests that mass media approaches to drug education are likely to be as effective in rural areas and smaller towns as they are among urban adolescents. Implications for television programming are discussed. 相似文献
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140.
Gallup macropartisanship varies more over time than aggregatemeasures of partisanship employing the standard Michigan SurveyResearch Center (SRC) party identification measure, but previousanalyses do not provide direct evidence about why Gallup macropartisanshipis more variable. Although these differences could result fromthe short-term focus of the Gallup party affiliation question,aggregate-level analyses cannot test the effects of questionwording directly. Between March and October 1992, we conducteda series of question-wording experiments, employing six statewidecomputer-assisted telephone interview (CATI) surveys of Michiganadults, including a four-wave panel study. Our analyses stronglysuggest that the Gallup measure responds more to short-termpolitical conditions and clearly demonstrate that the Gallupmeasure is less stable over time. These individual-level resultshelp explain why Gallup macropartisanship varies more over timethan aggregate measures of partisanship employing the standardSRC measure and raise questions about the degree to which onecan generalize from analyses using the Gallup data to the researchliterature on party identification. 相似文献