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961.
Why Does Immigrant Trip Duration Vary Across U.S. Destinations?   总被引:1,自引:0,他引:1  
Objective . This article explores the factors that lead to differences in immigrant trip duration across U.S. destinations. Methods . Using data from the Mexican Migration Project and the 1970, 1980, and 1990 U.S. Censuses, we estimate discrete-time hazard models of the probability of return for unauthorized male migrants. Results . We find three patterns of migration for undocumented migrants across U.S. destinations: semi-permanent and permanent migration to urban areas; temporary migration to agricultural areas; and sojourner, or cyclical, migration to border regions. These patterns depend on the characteristics of the immigrant population that moves to each destination, in addition to the opportunities available to migrants in each destination. However, all these factors are mediated by social and institutional conditions at the destination. Conclusions . The findings of this study reiterate the importance of economic opportunities as an important predictor of not only migration to, but also length of stay in, the United States. Dynamic regions not only attract more immigrants, but they also attract a more permanent population of migrants.  相似文献   
962.
963.
964.
The compelling quality of the Global Change simulation study ( Altemeyer, 2003 ), in which high RWA (right-wing authoritarianism)/high SDO (social dominance orientation) individuals produced poor outcomes for the planet, rests on the inference that the link between high RWA/SDO scores and disaster in the simulation can be generalized to real environmental and social situations. However, we argue that studies of the Person × Situation interaction are biased to overestimate the role of the individual variability. When variables are operationalized, strongly normative items are excluded because they are skewed and kurtotic. This occurs both in the measurement of predictor constructs, such as RWA, and in the outcome constructs, such as prejudice and war. Analyses of normal linear statistics highlight personality variables such as RWA, which produce variance, and overlook the role of norms, which produce invariance. Where both normative and personality forces are operating, as in intergroup contexts, the linear analysis generates statistics for the sample that disproportionately reflect the behavior of the deviant, antinormative minority and direct attention away from the baseline, normative position. The implications of these findings for the link between high RWA and disaster are discussed.  相似文献   
965.
966.
A request for euthanasia or assistance in suicide usually derives from severe patient distress and indicates significant suffering. Although the Hippocratic purview of medicine requires that suffering be acknowledged, its causes be identified, and that steps be taken to provide adequate relief, an appreciation of the diversity of factors that may contribute to suffering underscores the need for methodical assessment and familiarity with a range of therapeutic strategies. It may be argued that when other options to effectively relieve suffering are available, euthanasia and assisted suicide fall outside of the purview of Hippocratic medicine. Given the existence of other options, the capacity for human maleficence, and the lack of resources currently allocated to the relief of suffering, this paper presents a number of reservations regarding the legalization of euthanasia and assisted suicide. In addition, it is suggested that the current community focus on the issue of inadequately relieved suffering should be harnessed to work toward the provision of care that would diminish the impression that elective death is necessary to ensure adequate relief.  相似文献   
967.
Voters satisfy maximin or maximax in their choices between sets of alternatives and secure a Pareto improvement by all voting strategically under simple majority voting for particular sincere preferences. Thus the assumption that strategic voting is a bad thing is challenged and the idea that we should reject voting because of the possibility of misrepresentation dismissed.  相似文献   
968.
This study documents two empirical facts using matched employer–employee data for Denmark and Portugal. First, workers who are hired last, are the first to leave the firm. Second, workers' wages rise with seniority, where seniority is defined as a worker's tenure relative to the tenure of his colleagues. Controlling for tenure, the probability of a worker leaving the firm decreases with seniority. The increase in expected seniority with tenure explains a large part of the negative duration dependence of the separation hazard. Conditional on ten years of tenure, the wage differential between the 10th and the 90th percentiles of the seniority distribution is 1.1–1.4 percentage points in Denmark and 2.3–3.4 in Portugal.  相似文献   
969.
In this article, we model the relationship between two circular variables using the circular regression models, to be called JS circular regression model, which was proposed by Jammalamadaka and Sarma (1993). The model has many interesting properties and is sensitive enough to detect the occurrence of outliers. We focus our attention on the problem of identifying outliers in this model. In particular, we extend the use of the COVRATIO statistic, which has been successfully used in the linear case for the same purpose, to the JS circular regression model via a row deletion approach. Through simulation studies, the cut-off points for the new procedure are obtained and its power of performance is investigated. It is found that the performance improves when the resulting residuals have small variance and when the sample size gets larger. An example of the application of the procedure is presented using a real dataset.  相似文献   
970.
Crawling experience was recently linked to crawling and walking infants’ avoidance of falling on real and water cliffs, whereas walking experience had no effect on walkers’ avoidance behavior (Burnay et al., 2021). In the current study, the behavior of 25 infants was analyzed on the Real Cliff/Water Cliff apparatus using a longitudinal study design. Infants were tested as experienced crawlers (Mcrawling = 2.93 months, SD = 1.07), novice walkers (Mwalking = 0.68 months, SD = 0.29), and experienced walkers (Mwalking = 4.90 months, SD = 0.92). Infants avoided falling on both cliffs when tested as experienced crawlers and their behavior was not different when tested as novice or experienced walkers. These findings confirmed the effect of crawling experience on crawling and walking infants’ avoidance of falls from heights and into water and the transfer of perceptual learning from crawling to walking postures.  相似文献   
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