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41.
While the literature has indeed confirmed a general tendency linking small and medium enterprises (SMEs) to a dynamic of greater job creation, there is little available evidence on what has happened to job quality since the financial crisis. Through a representative sample of 5311 employees in 2008 (first year of job destruction) and 4925 employees in 2010 (last year for which data were available), and using a two-stage structural equation model, this article empirically analyses the multidimensional determinants of job quality, by enterprise-size class, in Spain. The research has revealed three main results. First, job quality in Spain improved in all enterprises, regardless of their size, during the early years of the recession. Second, the greatest improvements were found in SMEs. Although job quality was already better in SMEs than in large enterprises in 2008, the differences between them subsequently widened. Third, this accelerated divergence was explained by the following dimensions: working conditions, work intensity, health and safety at work, and work–life balance. These dimensions were much more positive in SMEs. Employment-related public policy should therefore focus more specifically on SMEs. There are two reasons for this. First, despite the recession, SMEs have shown themselves to be key factors in the explanation of job quality. Second, by making changes to their value generation model, they could continue to drive the creation of better quality jobs.  相似文献   
42.
This paper develops a method for handling two-class classification problems with highly unbalanced class sizes and misclassification costs. When the class sizes are highly unbalanced and the minority class represents a rare event, conventional classification methods tend to strongly favour the majority class, resulting in very low detection of the minority class. A method is proposed to determine the optimal cut-off for asymmetric misclassification costs and for unbalanced class sizes. Monte Carlo simulations show that this proposal performs better than the method based on the notion of classification accuracy. Finally, the proposed method is applied to empirical data on Italian small and medium enterprises to classify them into default and non-default groups.  相似文献   
43.
For a large series of IxJ tables, each containing two observations, the bias of the maximum likelihood estimates of log linear partial association parameters is shown to be equal to the parameters, regardless of the size of I and J. The partial association considered is that between row and column variables; the three way interactions are assumed to be O. This is a generalization of Andersen's results (1973a, 1973b) for a series of 2x2 tables.  相似文献   
44.
The literature on sequential estimation problems for negative exponential populations has been reviewed here, We attempt to bring in all the published and unpublished materials known to us in a fairly coherent fashion. Both the concepts and theoretical findings are discussed.  相似文献   
45.
This paper deals with a longitudinal semi‐parametric regression model in a generalised linear model setup for repeated count data collected from a large number of independent individuals. To accommodate the longitudinal correlations, we consider a dynamic model for repeated counts which has decaying auto‐correlations as the time lag increases between the repeated responses. The semi‐parametric regression function involved in the model contains a specified regression function in some suitable time‐dependent covariates and a non‐parametric function in some other time‐dependent covariates. As far as the inference is concerned, because the non‐parametric function is of secondary interest, we estimate this function consistently using the independence assumption‐based well‐known quasi‐likelihood approach. Next, the proposed longitudinal correlation structure and the estimate of the non‐parametric function are used to develop a semi‐parametric generalised quasi‐likelihood approach for consistent and efficient estimation of the regression effects in the parametric regression function. The finite sample performance of the proposed estimation approach is examined through an intensive simulation study based on both large and small samples. Both balanced and unbalanced cluster sizes are incorporated in the simulation study. The asymptotic performances of the estimators are given. The estimation methodology is illustrated by reanalysing the well‐known health care utilisation data consisting of counts of yearly visits to a physician by 180 individuals for four years and several important primary and secondary covariates.  相似文献   
46.
为了研究离心泵在输送黏性介质时,叶轮出口角对泵性能的影响,采用FLUENT软件,对2种不同叶轮出口角的 离心泵,分别在清水和5种不同黏性的油性介质下,进行数值模拟分析,预测离心泵在各工况下的水力性能。结果表明: 输送介质为清水时,增大出口角能提高扬程但会降低水力效率;介质运动黏度介于10. 80~ 65. 00 mm2/s时,增加叶轮出 口角能同时提高扬程和效率;介质运动黏度≥65. 00 1111112/S时,增加出口角不能改善其水力性能。文章研究结果能改善 离心泵的水力设计方法,确保泵的高效运行。  相似文献   
47.
由于螺杆泵几何结构及流体流动状态较为复杂,其压力分布和速度等特性很难用数学解析法来分析计算。本文利用参数化设计模块建立双螺杆泵Q形对称型螺杆三维模型,构建双螺杆流道的流场分析模型,运用有限元分析方法得出了双螺杆泵流道内压力场和速度场分布规律。结果表明:流体在流道中的流速分布具有规律性,整个流道的流场速度高低交替变化,在螺杆与衬套间隙处的流动为层流,螺旋面接触区内的流动为复杂的湍流,离螺杆啮合区近的螺旋槽内易发生涡流。本研究结果对于了解双螺杆泵螺杆工况下的性能情况具有重要的参考价值。  相似文献   
48.
手机媒体是一种继报纸、广播、电视、网络四大媒体之后出现的、以手机为载体的媒体,手机媒体传播的特点是即时的大众传播和人际传播的结合,我们可以称之为"人际大众传播"。本文认为,作为"跨媒体"时代信息传播的重要成员,手机媒体对大众传播的广泛参与,优化了传播过程,弥补了以往大众传播的缺陷,同时也打破了主流媒体原有的传播思路与格局,对主流媒体产生了极大的影响。  相似文献   
49.
自我和谐与社会和谐——构建和谐社会的心理学解读   总被引:4,自引:0,他引:4  
和谐社会即构成社会的各个团体及个人之间存在一定的差别(可以表现为社会地位、经济收入水平、个人行为方式以及个性特点等方面),但彼此之间又能够和谐相处的社会.构建和谐社会的努力包括保持自我和谐、人际和谐及人与自然的和谐,从心理学出发,这三方面的工作除了物质、制度和政策层面的努力以外,更重要的是确保这些努力能够被个体准确感知和把握.心理学服务于构建和谐社会的主要领域包括对心理健康和幸福感的研究、对个人成长与成功的研究以及对团体动力学的研究.解决和处理好我国心理学研究中目前存在的问题,对于顺利完成党中央提出的构建和谐社会的使命具有很好的理论意义和实践价值.  相似文献   
50.
《文艺报》与中国当代文学批评有着不可分割的关联。此种关联有助于我们梳理刊物本身与文学批评舆论建构的密切关系。在新时期文学批评舆论建构的初始阶段,《文艺报》以"介入与建构"彰显着主导文学评论刊物的媒介价值观与立场。这主要表现在总结态势与成绩",漫谈"文风的"回归"与延续,刊物栏目的"回归"与"新创",举办座谈会和编发会议报告、讲话及读者来稿",作品讨论"的出现与坚守,以及舆论的"视觉"诉求等等。  相似文献   
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