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1.
In this cross-country study we drew on job demands-resources theory to investigate whether psychological empowerment mediates the positive association between structural empowerment and work engagement and, consequently, task performance and intention to quit. A total of 1033 employees working in the service sector in Spain (N = 515) and the United Kingdom (N = 518) participated in the study. Multi-group structural equation modeling analyses revealed that psychological empowerment partially mediated the positive relationship between structural empowerment and work engagement, and that work engagement associated positively with task performance and negatively with intention to quit. Invariance analyses suggested that the positive link between psychological empowerment and work engagement was stronger for employees working in the UK than in Spain, providing support for partial structural invariance of the hypothesized model. These findings suggest that psychological empowerment is an underlying mechanism that may explain why structural empowerment relates positively to work engagement with implications for theory (i.e., extend the nomological network of the investigated constructs) and management practice (e.g., emphasize the role of structural empowerment for work design).  相似文献   
2.
针对磷酸酯/Al3+ 交联的油基压裂液交联速度慢,交联剂溶解性慢、稳定性差和价格高等缺点,首次对磷酸酯/Fe3+ 交联的油基压裂液体系进行了研究。通过对铁交联剂体系的优化,筛选一种磷酸酯/Fe3+ 交联的新型交联剂体系,并对磷酸酯/Fe3+ 油基冻胶压裂液性能进行了评价。结果表明:采用30%Fe2(SO4)3+15% 二乙醇胺+55% 水制备的新型交联剂体系,直接与磷酸酯混合即可形成油基冻胶,其性能不受放置时间的影响,交联速度快,成胶性能好,10 min 就可达到最大黏度;压裂液的抗温抗剪切性能高,与常规铝交联剂体系比较,压裂液成胶速度提高了20 倍,压裂液的抗温能力由原来100 ℃提高到135 ℃,并且压裂液的破胶性和滤失性等性能均能达到压裂施工的要求。  相似文献   
3.
This study demonstrates the analytical leverage gained from considering the entire college pipeline—including the application, admission and graduation stages—in examining the economic position of various groups upon labor market entry. The findings, based on data from three elite universities in Israel, reveal that the process that shapes economic inequality between different ethnic and immigrant groups is not necessarily cumulative. Field of study stratification does not expand systematically from stage to stage and the position of groups on the field of study hierarchy at each stage is not entirely explained by academic preparation. Differential selection and attrition processes, as well as ambition and aspirations, also shape the position of ethnic groups in the earnings hierarchy and generate a non-cumulative pattern. These findings suggest that a cross-sectional assessment of field of study inequality at the graduation stage can generate misleading conclusions about group-based economic inequality among workers with a bachelor’s degree.  相似文献   
4.
Multinomial logit (also termed multi-logit) models permit the analysis of the statistical relation between a categorical response variable and a set of explicative variables (called covariates or regressors). Although multinomial logit is widely used in both the social and economic sciences, the interpretation of regression coefficients may be tricky, as the effect of covariates on the probability distribution of the response variable is nonconstant and difficult to quantify. The ternary plots illustrated in this article aim at facilitating the interpretation of regression coefficients and permit the effect of covariates (either singularly or jointly considered) on the probability distribution of the dependent variable to be quantified. Ternary plots can be drawn both for ordered and for unordered categorical dependent variables, when the number of possible outcomes equals three (trinomial response variable); these plots allow not only to represent the covariate effects over the whole parameter space of the dependent variable but also to compare the covariate effects of any given individual profile. The method is illustrated and discussed through analysis of a dataset concerning the transition of master’s graduates of the University of Trento (Italy) from university to employment.  相似文献   
5.
The generalized half-normal (GHN) distribution and progressive type-II censoring are considered in this article for studying some statistical inferences of constant-stress accelerated life testing. The EM algorithm is considered to calculate the maximum likelihood estimates. Fisher information matrix is formed depending on the missing information law and it is utilized for structuring the asymptomatic confidence intervals. Further, interval estimation is discussed through bootstrap intervals. The Tierney and Kadane method, importance sampling procedure and Metropolis-Hastings algorithm are utilized to compute Bayesian estimates. Furthermore, predictive estimates for censored data and the related prediction intervals are obtained. We consider three optimality criteria to find out the optimal stress level. A real data set is used to illustrate the importance of GHN distribution as an alternative lifetime model for well-known distributions. Finally, a simulation study is provided with discussion.  相似文献   
6.
Although field experiments have documented the contemporary relevance of discrimination in employment, theories developed to explain the dynamics of differential treatment cannot account for differences across organizational and institutional contexts. In this article, I address this shortcoming by presenting the main empirical findings from a multi‐method research project, in which a field experiment of ethnic discrimination in the Norwegian labour market was complemented with forty‐two in‐depth interviews with employers who were observed in the first stage of the study. While the experimental data support earlier findings in documenting that ethnic discrimination indeed takes place, the qualitative material suggests that theorizing in the field experiment literature have been too concerned with individual and intra‐psychic explanations. Discriminatory outcomes in employment processes seems to be more dependent on contextual factors such as the number of applications received, whether requirements are specified, and the degree to which recruitment procedures are formalized. I argue that different contexts of employment provide different opportunity structures for discrimination, a finding with important theoretical and methodological implications.  相似文献   
7.
Simulation results are reported on methods that allow both within group and between group heteroscedasticity when testing the hypothesis that independent groups have identical regression parameters. The methods are based on a combination of extant techniques, but their finite-sample properties have not been studied. Included are results on the impact of removing all leverage points or just bad leverage points. The method used to identify leverage points can be important and can improve control over the Type I error probability. Results are illustrated using data from the Well Elderly II study.  相似文献   
8.
21世纪以来,中国农村治理研究陷入了本土化与主体性双重困境,中国农村社会基础的深度转型,农村研究方法的缺陷以及大规模村庄研究的局限,要求中国农村研究回归深度的村庄研究,尊重农民主体性。在回归村庄研究的方法论上,文章认为要突破国家政权建设理论等研究视角的局限,把市场化这一变量纳入分析视野中。村庄主位、农民主体、市场化过程同国家宏观治理体系的互动逻辑,应该构成后中国农村治理研究时代的主要内容。  相似文献   
9.
Increased juvenile delinquency can be seen as an indicator for a deteriorating social fabric under conditions of rapid social change. Criminological theories suggest, however, that such conditions do not per se produce delinquency: They force youth into prodelinquent leisure activities with peers, leading to an endorsement of delinquent behavior and offering the infrastructure for it. Resources acquired in family and public life, however, may prevent youth from drifting into such prodelinquent leisure activities and indirectly from delinquent behavior. Empirical tests of these hypotheses have to employ simultaneous analyses of societal-level and individual-level data. On the basis of an international youth study, the paper undertakes such an analysis: In the years 1992–95, data from 42 independent samples of seventh graders from East and West Germany, Poland, Russia, Bulgaria, Slovakia, Hungary, Czechia, and Greece were surveyed. Data on deviant school behavior, delinquent drift, nurturant parenting, and subjective feelings of justice in public were obtained from 7282 thirteen- to fourteen-year-olds. Processes of rapid social change were incorporated as data on changes in GNP in the years proceeding the surveys. Analyses show that delinquent drift is a valid predictor of deviant school behavior only on the individual level. The extent to which adolescents engage in prodelinquent peer activities depends more on the cultural context in which adolescents live than on their personal experience in the family and in public. Nurturant parenting does, however, covary negatively with deviant school behavior irrespective of level of analysis.  相似文献   
10.
烟毒影响近代中国社会至深且巨 ,南京国民政府自成立之日起便展开对这一社会问题的治理工作。抗战前十年其禁烟政策历经“寓禁于征”、断禁和渐禁三个阶段的演变 ,在禁烟领域作出了自己的努力 ,并取得阶段性成果 ,北洋军阀时期烟毒大泛滥的局面得到基本扼制。  相似文献   
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