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821.
This paper makes two contributions to the literature on the effects of wealth on health. First, it deals with reverse causality and omitted variable bias by exploiting exogenous variation in inherited wealth generated by the repeal of the Swedish inheritance tax. Second, it analyzes responses in health outcomes through the use of administrative registers. The results show that increased wealth has limited short to medium run impacts on objective adult health. This is in line with what has previously been reported in the literature.  相似文献   
822.
This study is the first to comprehensively examine the effect of state anti-bullying laws (ABLs) on school safety and youth violence. Using existing data from the Youth Risk Behavior Surveys and the Uniform Crime Reports, and newly-collected data on school shootings, we find little evidence that the typical state ABL is effective in improving school safety and student well-being. However, this null finding masks substantial policy heterogeneity. State mandates that require school districts to implement strong, comprehensive anti-bullying policies are associated with a 7 to 13 % reduction in school violence and an 8 to 12 % reduction in bullying. In addition, our results show that strong anti-bullying policy mandates are associated with a reduction in minor teen school shooting deaths and violent crime arrests, suggesting potentially important spillover effects.  相似文献   
823.
Despite the historical highs for age at first marriage, little is known about the causal relationship between marriage delay and wages, and more importantly, the mechanisms driving such relationship. We attempt to fill the void. Building on an identification strategy proposed in Dahl (Demography 47:689–718, 2010), we first establish the causal wage effects of marriage delay. We then propose ways to distinguish among competing theories and hypotheses, as well as the channels through which marriage delay affects wages. Specifically, we take advantage of their different implications for causal relationship, across gender and sub-populations. We reach two conclusions. First, we find a positive causal impact of marriage delay on wages, with a larger effect for women. Comparison of IV and OLS estimates suggests that the observed relationship between marriage delay and wages is attributed to both selection in late marriages and true causal effects. Second, we find strong evidence that the positive, causal effects are almost exclusively through increased education for both men and women.  相似文献   
824.
We investigate the relationship between economic freedom and international migration for the 1980–2010 period using a dataset on migration from 91 emerging countries to the 20 most attractive OECD destination countries. We find that more economic freedom at home discourages high-skilled migration, but not low-skilled migration. The negative association between economic freedom and high-skilled emigration also holds when we estimate (dynamic) panel models that allow for endogeneity in the economic freedom-migration nexus. In sum, our findings suggest that high-skilled migration is especially responsive to the economic incentives resulting from economic freedom.  相似文献   
825.
This paper stems from the observation that there are two worldwide trends, pension reform and population ageing, and asks whether the two may be related. Exploring the cases of pension reform in different countries, we find that, although they are very different, the cases share a common characteristic: they shift risks away from workers towards those who are retired. Furthermore, population ageing, by increasing the weight of the elderly relative to working generations, raises the price of intergenerational risk sharing. Combining these findings, we argue and show formally that pension reform can be seen as a welfare-best response to population ageing.  相似文献   
826.
Early in the 30-year HIV/AIDS pandemic in Sub-Saharan Africa, epidemiological studies identified formal education attainment as a risk factor: educated Sub-Saharan Africans had a higher risk of contracting HIV/AIDS than their less educated peers. Later demographic research reported that by the mid-1990s the education effect had reversed, and education began to function as a social vaccine. Recent counter-evidence finds a curvilinear pattern, with the association between educational attainment and HIV/AIDS infection changing from positive to negative across the education gradient. To reconcile these inconsistent conclusions, a hypothesis is developed and tested that education at early stages functioned as a risk factor and later functioned (and continues to function) as a social vaccine. We reason that this shift in the direction of the education effect was concurrent with changes in the public health environment in SSA that early on heightened material benefits from educational attainment but later heightened cognitive benefits from schooling. Using the 2003/2004 Demographic Health Surveys from four Sub-Saharan African countries (Cameroon, Ghana, Kenya and Tanzania), we tested this hypothesis (differential effects of schooling) using non-linear regression analysis (probit), identifying the different public health periods and controlling for confounding factors. The results support the hypothesis that the education effect shifted historically in the HIV/AIDS pandemic in SSA as we hypothesized.  相似文献   
827.
828.
The Kidney Exchange Problem (KEP) is a combinatorial optimization problem and has attracted the attention from the community of integer programming/combinatorial optimisation in the past few years. Defined on a directed graph, the KEP has two variations: one concerns cycles only, and the other, cycles as well as chains on the same graph. We call the former a Cardinality Constrained Multi-cycle Problem (CCMcP) and the latter a Cardinality Constrained Cycles and Chains Problem (CCCCP). The cardinality for cycles is restricted in both CCMcP and CCCCP. As for chains, some studies in the literature considered cardinality restrictions, whereas others did not. The CCMcP can be viewed as an Asymmetric Travelling Salesman Problem that does allow subtours, however these subtours are constrained by cardinality, and that it is not necessary to visit all vertices. In existing literature of the KEP, the cardinality constraint for cycles is usually considered to be small (to the best of our knowledge, no more than six). In a CCCCP, each vertex on the directed graph can be included in at most one cycle or chain, but not both. The CCMcP and the CCCCP are interesting and challenging combinatorial optimization problems in their own rights, particularly due to their similarities to some travelling salesman- and vehicle routing-family of problems. In this paper, our main focus is to review the existing mathematical programming models and solution methods in the literature, analyse the performance of these models, and identify future research directions. Further, we propose a polynomial-sized and an exponential-sized mixed-integer linear programming model, discuss a number of stronger constraints for cardinality-infeasible-cycle elimination for the latter, and present some preliminary numerical results.  相似文献   
829.
This study examined racial–ethnic minority and white identified participants’ perceptions of racial microaggressions in four video scenarios involving a white professor and a black student. Participants (N = 261) were randomly assigned to observe a one of the four video conditions. The video involved an interaction with no microaggression, a very ambiguous microaggression, an ambiguous microaggression, or an overt microaggression. Participants rated their observations of (a) negative emotions toward the committer (white professor) and receiver (black student) of the microaggression, (b) positive emotions toward the committer and receiver of the microaggression, (c) perceptions on the degree of biasedness of committer, and (d) degree of positive perceptions of the committer. Analysis compared ratings of two groups, including racial–ethnic minority and white observers. We found a significant difference between the overt condition and other three conditions on negative emotions, positive emotions, and attributions of the professor (i.e., cultural biasedness and positive perceptions). However, there were no differences between the no microaggression, very ambiguous, and ambiguous conditions. No significant differences between racial–ethnic minority and white participants’ ratings were detected. Implications for training, practice, and future research are offered in our discussion.  相似文献   
830.
Many Americans endorse a colorblind racial ideology, meaning they strive to “not see race” and emphasize sameness and equal distribution of resources across racial lines. Currently, there is an absence of studies examining the personality and individual difference correlates of racial colorblindness. The current study investigated the association between three different aspects of racial colorblindness (unawareness of racial privilege, unawareness of institutional discrimination, and unawareness of blatant racism) and the Big 5, empathy, and aggression in white undergraduates. Our results revealed two divergent patterns. Unawareness of racial privilege was related to lower openness and perspective taking, but more empathic concern, whereas unawareness of blatant racism and unawareness of institutional discrimination were related to lower agreeableness, perspective taking, and empathic concern. These results are discussed in relation to the broader literature on prejudice and personality.  相似文献   
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