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The paper uses a three-factor (capital, low- and high-skill labor), two-household (low- and high-skill individuals), two-sector trade model to analyze the determinants of voter attitudes towards immigration under direct democracy, and to identify factors that would be coherent with both the observed increase in the skilled–unskilled wage differential and the stiffening attitudes towards low-skill capital-poor immigration. If the import-competing sector is intensive in the use of low-skill labor, and capital is the middle factor, an improvement in the terms of trade or neutral technical progress in the exporting sector leads nationals to oppose immigration of capital-poor low-skill households. An increase in income inequality is also likely to stiffen attitudes towards this type of capital-poor, low-skill immigration prevalent in Europe until recently.  相似文献   
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Canada's wheat grading system is largely based on visual criteria and it is based on relatively high quality standards. A strict varieties licensing system exists to maintain the integrity of the grade standards. One of the consequences of the licensing system is that higher yielding, lower or different quality wheats have not been grown in Canada until recently. The basic objective of this paper is to examine some of the consequences of the regulatory strategy of limiting wheat production to the traditional high quality wheats. This question is analyzed in the context of important changes in the international grain markets. Using a partial equilibrium trade model this paper estimates that if higher yielding wheats were permitted to be grown, annual producer gains would be 5 to 17 percent of current net farm income.
Le classement des blés au Canada est basé sur des critères visuels qui sont de hautes qualités. Le système actuel d'homologation des variétés est tel que l'intégrité de ce système est maintenue. En conséquent, ce système n'a pas encouragé la cultivation des blés de hauts rendements ou des varietés différentes que tout récemment. L'objectif principal de cette étude est d'examiner quelques unes des conséquences de la stratégic de la réglementation visant à limiter la production du blé aux variétés de hautes qualités. Cette question est adressée dans le contexte des changements importants qui ont eu lieu dans le marché international des grains. A l'aide d'un modèle d'équilibre partiel des échanges, la présente étude démontre gu'en permettant la production des blés de hauts rendements, le gain annuel aux producteurs serait de 5 à 17 pourcent du revenue agricole net.  相似文献   
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The extra vulnerability of industrializing countries to environmental problems and industrial accidents cannot be understood or solved by a ‘normal’ scientific analysis. Aspects of the social and institutional context must be included, through analyses based on post-normal science. The standard two-dimensional classification of PNS is modified to have axes ‘social ‘and institutional vulnerabilities’ and ‘complexity of technological hazards’. The analysis is mainly applied to the case of the relatively rare accidents with catastrophic potential. In these, the deaths per accident in India, Mexico and Brazil are much greater than in the industrialized countries. This discrepancy arises partly from location of such plants near residential communities for marginalized workers and their families. Other socio-political factors are relevant, as the role of these countries in the global production system, the enforcement of safety and planning laws, quality of housing, and lifestyle of residents. Reducing the vulnerability of industrializing countries will therefore require major social policies and a comprehension of the limits of the normal scientific and economic approaches to such problems.  相似文献   
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It appears that programme development in technology education is emerging from an atheoretical perspective. This could be attributed to the absence/neglect of conceptual frameworks (philosophical underpinning) in the development of programmes in technology education. This article explores the role of the content dimension of the 'essential features' of technology and technology education in OBE (Outcomes Based Education) related programme development. An instructional programme was developed using criteria derived from the essential features of technology and technology education. In order to gauge learners' experience, in relation to these essential features, a qualitative case study involving 20 learners was undertaken at a College of Education. Engagement with theprogramme proved to be an empowering experience for the learners who had hitherto not had the opportunity to experience a formal programme in technology education. Although it could not be proved conclusively that cognitive development had occurred, positive inter-dependence,shared responsibility, social skills and enhanced learning were evident. The study has shown that criteria derived from the 'essential features' of technology and technology education could serve as a reliable yardstick to measure the extent of learning in relation to these essential features  相似文献   
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In this paper we compare alternative asymptotic approximations to the power of the likelihood ratio test used in covariance structure analysis for testing the fit of a model. Alternative expressions for the noncentrality parameter (ncp) lead to different approximations to the power function. It appears that for alternative covariance matrices close to the null hypothesis, the alternative ncp's lead to similar values, while for alternative covariance matrices far from Ho the different expressions for the ncp can conflict substantively. Monte Carlo evidence shows that the ncp proposed in Satorra and Saris (1985) gives the most accurate power approximations.  相似文献   
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