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51.
South Africa is a regional hub for migration on the African continent and is home to a growing documented international migrant community. Foreigners in the country, however, often face violations of their established rights and are the victims of abuse. This paper examines public support for policies that would exclude international migrants from the country. Data from the 2013 South African Social Attitudes Survey, a nationally representative opinion poll (N = 2739) of all adults in the country, are used. This poll found that many South Africans favoured restrictive immigration policies and opposed granting foreigners the same rights as citizens. Multivariate analysis is employed to discern determinants of this opposition. Respondents’ perceptions of the population sizes of foreigners in their communities did not affect support for inclusion. It can be inferred, therefore, that the growth of the immigrant population has not provoked exclusionary attitudes in the country. Rather, results revealed, it is national pride (cultural versus political) and fears about the consequences of immigration that drive such attitudes. Programmes and policies designed to improve public perceptions of how foreigner impact society and the promotion of a nationalism characterised by inclusive multicultural civic patriotism may improve public support for the inclusion of international immigrants.  相似文献   
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This paper outlines decomposition methods for assessing how exposure affects prevalence and cumulative relative risk. Let     x     denote a vector of exogenous covariates and suppose that a single dimension of time   t   governs two event processes     T 1  and   T 2.    If the occurrence of the event     T 1    determines entry into the risk of the event     T 2,    then subgroup variation in     T 1    will affect the prevalence     T 2,    even if subgroups in the population are otherwise identical. Although researchers often acknowledge this phenomenon, the literature has not provided procedures to assess the magnitude of an exposure effect of     T 1    on the prevalence of     T 2.    We derive decompositions that assess how variation in exposure generated by direct and indirect effects of the covariates     x     affect measures of absolute and relative prevalence of     T 2.    We employ a parametric but highly flexible specification for baseline hazard for the     T 1  and   T 2    processes and use the resulting parametric proportional hazard model to illustrate the direct and indirect effects of family structure when     T 1    is age at first sexual intercourse and     T 2    is age at a premarital first birth for data on a cohort of non-hispanic white U.S. women.  相似文献   
54.
We develop a mathematical optimization model at the intersection of homeland security and immigration, that chooses various immigration enforcement decision variables to minimize the probability that a terrorist can successfully enter the United States across the U.S.-Mexico border. Included are a discrete choice model for the probability that a potential alien crosser will attempt to cross the U.S.-Mexico border in terms of the likelihood of success and the U.S. wage for illegal workers, a spatial model that calculates the apprehension probability as a function of the number of crossers, the number of border patrol agents, and the amount of surveillance technology on the border, a queueing model that determines the probability that an apprehended alien will be detained and removed as a function of the number of detention beds, and an equilibrium model for the illegal wage that balances the supply and demand for work and incorporates the impact of worksite enforcement. Our main result is that detention beds are the current system bottleneck (even after the large reduction in detention residence times recently achieved by expedited removal), and increases in border patrol staffing or surveillance technology would not provide any improvements without a large increase in detention capacity. Our model also predicts that surveillance technology is more cost effective than border patrol agents, which in turn are more cost effective than worksite inspectors, but these results are not robust due to the difficulty of predicting human behavior from existing data. Overall, the probability that a terrorist can successfully enter the United States is very high, and it would be extremely costly and difficult to significantly reduce it. We also investigate the alternative objective function of minimizing the flow of illegal aliens across the U.S.-Mexico border, and obtain qualitatively similar results.  相似文献   
55.
Russia’s transition to a market economy has been accompanied by serious, and in some ways unanticipated, disruptions of the existing social welfare system. The social policy dilemma has become a contentious issue in the national political arena. This paper examines the debate on the relationship between social welfare and democratization in post-communist Russia, exploring the case of pensions for the elderly. Although the causes of the pension crisis are complex and rooted in institutional difficulties, the state’s fiscal weakness alone does not explain the difficulties and controversies associated with Russia’s pension crisis. Analysis of the assumptions and principles of pension policy during the Soviet era and perestroika reveals that Russia today is caught between contradictory and competing discourses over citizens’ entitlement to pensions: Is an old-age pension to be considered a reward distributed by a prosperous society, or a basic and inviolable human right? Although the Russian government has used an argument that in effect makes pensions conditional on government resources, citizen and opposition protest has to some extent compelled the Russian government to be increasingly sensitive to demands for guaranteed pensions.  相似文献   
56.
The outbreak of a highly communicable disease, SARS, in Asia in 2003 has revealed the health risk of living in a high-density environment. To show the important connection between human health and environmental quality, this study surveys the prevalence of sick building syndrome (SBS) among apartment residents and their evaluation of indoor environmental quality (IEQ). Based on a sample of 748 households living in Hong Kong, two interesting findings are revealed: (1) nasal discomfort was the commonest home-related SBS symptom despite the absence of any central ventilation system in apartment buildings; (2) noise, rather than ventilation, was the major IEQ problem perceived by residents. Our statistical analysis further showed that residents with SBS symptoms were less satisfied with their IEQ than those without. That is, despite a positive evaluation of specific IEQ criteria with respect to the building residents lived in, if they reported feeling SBS related symptoms, the overall IEQ evaluation of their building could still be negative. This perception bias gives rise to a sample selection problem in measuring perceived IEQ, which has implications on housing management practices and the formulation of a healthy housing policy.  相似文献   
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The Fish Invasiveness Scoring Kit (FISK) is currently one of the most popular pre‐screening tools for freshwater fishes. A recent upgrade has ensured its wider climatic relevance to countries with subtropical regions. This enhancement is of particular importance to Australia, which encompasses tropical, arid, and temperate zones, and where the introduction of non‐native fish species poses a significant risk to biodiversity. In this study, 55 fish species previously evaluated in a U.K.‐based calibration of FISK are reassessed for their potential invasiveness in the Murray‐Darling Basin (MDB; southeastern Australia), the continent's largest catchment encompassing arid and temperate climates. Approximately half of the species were classed as “medium risk” and the other half as “high risk,” and the ≥19 threshold previously identified from the calibration study was confirmed. The three highest scoring species (common carp Cyprinus carpio carpio, goldfish Carassius auratus, and eastern mosquitofish Gambusia holbrooki) were those already present and invasive in the area, whereas nearly half of the tropical and subtropical species had lower scores compared to U.K. assessments, possibly because of climate change predictions of drier conditions across the MDB. There were some discordances between FISK and two Australian‐based assessment protocols, one of which is qualitative and the other represents a simplified version of FISK. Notably, the Australian origins of FISK should provide for an additional reason for further applications of the tool in other RA areas (i.e., drainage basins) of the continent, ultimately encouraging adoption as the country's reference screening tool for management and conservation purposes.  相似文献   
59.
Risk assessments are crucial for identifying and mitigating impacts from biological invasions. The Fish Invasiveness Scoring Kit (FISK) is a risk identification (screening) tool for freshwater fishes consisting of two subject areas: biogeography/history and biology/ecology. According to the outcomes, species can be classified under particular risk categories. The aim of this study was to apply FISK to the Iberian Peninsula, a Mediterranean climate region highly important for freshwater fish conservation due to a high level of endemism. In total, 89 fish species were assessed by three independent assessors. Results from receiver operating characteristic analysis showed that FISK can discriminate reliably between noninvasive and invasive fishes for Iberia, with a threshold of 20.25, similar to those obtained in several regions around the world. Based on mean scores, no species was categorized as “low risk,” 50 species as “medium risk,” 17 as “moderately high risk,” 11 as “high risk,” and 11 as “very high risk.” The highest scoring species was goldfish Carassius auratus. Mean certainty in response was above the category “mostly certain,” ranging from tinfoil barb Barbonymus schwanenfeldii with the lowest certainty to eastern mosquitofish Gambusia holbrooki with the highest level. Pair‐wise comparison showed significant differences between one assessor and the other two on mean certainty, with these two assessors showing a high coincidence rate for the species categorization. Overall, the results suggest that FISK is a useful and viable tool for assessing risks posed by non‐native fish in the Iberian Peninsula and contributes to a “watch list” in this region.  相似文献   
60.
The initial version (v1) of the Fish Invasiveness Scoring Kit (FISK) was adapted from the Weed Risk Assessment of Pheloung, Williams, and Halloy to assess the potential invasiveness of nonnative freshwater fishes in the United Kingdom. Published applications of FISK v1 have been primarily in temperate‐zone countries (Belgium, Belarus, and Japan), so the specificity of this screening tool to that climatic zone was not noted until attempts were made to apply it in peninsular Florida. To remedy this shortcoming, the questions and guidance notes of FISK v1 were reviewed and revised to improve clarity and extend its applicability to broader climatic regions, resulting in changes to 36 of the 49 questions. In addition, upgrades were made to the software architecture of FISK to improve overall computational speed as well as graphical user interface flexibility and friendliness. We demonstrate the process of screening a fish species using FISK v2 in a realistic management scenario by assessing the Barcoo grunter Scortum barcoo (Terapontidae), a species whose management concerns are related to its potential use for aquaponics in Florida. The FISK v2 screening of Barcoo grunter placed the species into the lower range of medium risk (score = 5), suggesting it is a permissible species for use in Florida under current nonnative species regulations. Screening of the Barcoo grunter illustrates the usefulness of FISK v2 as a proactive tool serving to inform risk management decisions, but the low level of confidence associated with the assessment highlighted a dearth of critical information on this species.  相似文献   
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