Data-driven tests of uniformity on product manifolds

Data-driven versions of Sobolev tests of uniformity on compact Riemannian manifolds are reviewed and their large-sample asymptotic properties are given. A variant which is suitable for product manifolds is introduced. Data-driven goodness-of-fit tests of multivariate distributions are derived from data-driven tests of uniformity on tori.     

人—工作匹配对员工工作幸福感的作用机制研究

基于社会交换理论,通过对209名员工2个时点的配对问卷调查,探讨了人—工作匹配和工作幸福感的关系及其作用机制,尤其是工作卷入的中介作用和工作技能的调节作用。结果发现:人—工作匹配对工作幸福感具有显著的正向作用;工作卷入在人—工作匹配和工作幸福感之间起部分中介作用;工作技能在人—工作匹配和工作卷入之间起调节作用,即工作技能水平越高,人—工作匹配对工作卷入的正向影响越强。     

The Gamma Distribution as a Mixture of Exponential Distributions

A gamma distribution with arbitrary scale parameter θ and shape parameter r < 1 can be represented as a scale mixture of exponential distributions.     

Working and caring for a disabled adopted child during a pandemic

Integrating work and family demands can be challenging for families caring for a child with one or more disabilities. The pandemic and its changes to work, schooling and service delivery potentially added to these challenges. This exploratory mixed methods study sought to understand how the pandemic affected adoptive parents' work–life fit and service use. A total of 200 participants responded to survey questions about parenting an adopted child with a disability prior to, and after, the onset of Covid-19. More than half of the parents (59.2%) reported that it was somewhat to very difficult to integrate both work and family demands. Parents with greater access to workplace flexibility and supportive supervisors had significantly less difficulties combining work and family. Families who reported more problems with accessing mental health services, special education and respite care reported significantly more challenges with work–family fit. Parents reported increased stress due to the pandemic changes, but many also shared positive changes such as more time for family. Online services were experienced as effective for some children and reduced time spent driving to appointments. Recommendations for workplace and social service practice and policy supporting adoptive parents of children with disabilities are discussed.     

The exact risk performance of a pre-test estimator in a heteroskedastic linear regression model under the balanced loss function

We examine the risk of a pre-test estimator for regression coefficients after a pre-test for homoskedasticity under the Balanced Loss Function (BLF). We show analytically that the two stage Aitken estimator is dominated by the pre-test estimator with the critical value of unity, even if the BLF is used. We also show numerically that both the two stage Aitken estimator and the pre-test estimator can be dominated by the ordinary least squares estimator when “goodness of fit” is regarded as more important than precision of estimation.     

SMOOTH TESTS FOR THE BIVARIATE POISSON DISTRIBUTION

A theorem of Rayner & Best (1989) is generalised to permit the construction of smooth tests of goodness of fit without requiring a set of orthonormal functions on the hypothesised distribution. This result is used to construct smooth tests for the bivariate Poisson distribution. The test due to Crockett (1979) is similar to a smooth test that assesses the variance structure under the bivariate Poisson model; the test due to Loukas & Kemp (1986) is related to a smooth test that seeks to detect a particular linear relationship between the variances and covariance under the bivariate Poisson model. Using focused smooth tests may be more informative than using previously suggested tests. The distribution of the Loukas & Kemp (1986) statistic is not well approximated by the x²distribution for larger correlations, and a revised statistic is suggested.     

PROPERLY RESCALED COMPONENTS OF SMOOTH TESTS OF FIT ARE DIAGNOSTIC

The paper illustrates a typical pitfall associated with a conventional interpretation of components of smooth tests of fit, for example the first nonzero components of the smooth tests for Poissonity, exponentiality, normality and the geometric distribution. In order to achieve a directed diagnosis concerning the kind of departure from a hypothesised model, an appropriate rescaling of components is necessary.     

Use of an empirical probability generating function for testing a Poisson model

We present a test of the fit to a Poisson model based on the empirical probability generating function (epgf). We derive the limiting distribution of the test under the Poisson hypothesis and show that a rescaling of it is approximately independent of the mean parameter in the Poisson distribution. When inspected under a simulation study over a range of alternative distributions, we find that this test shows reasonable behaviour compared to other goodness-of-fit tests like the Poisson index of dispersion and smooth test applied to the Poisson model. These results illustrate that epgf-based methods for anlyzing count data are promising.     

企业生命周期与股权集中度的匹配对企业绩效的影响——基于制造业上市公司的实证

文章从权变的视角,综合考虑企业所处的生命周期阶段,采用构图偏差的匹配方法评估企业生命周期与股权集中度的匹配程度,构建匹配程度与企业绩效的回归模型,并利用2012-2015年制造业上市公司的平衡面板数据进行实证。结果表明：成长阶段与较高股权集中度的匹配对企业绩效有正向影响;成熟阶段与分散状态下相对集中的股权模式相匹配对企业绩效有正向影响;衰退阶段与高度集中的股权模式相匹配对企业绩效有正向影响。     

The role of QMS in the relationship between innovation climate and performance

The emergence of new global competitors, the convergence of high-technology industries and the increasing speed and cost of technological development promises an increasingly uncertain environment for organisations, making adaptation to changes in the environment a central theme in the study of the organisation for both organisation theory and strategic management. This study thus seeks principally to verify that, while innovation and quality management (QM) alone do not possess the qualities required to provide organisations with sustainable competitive advantages, the bundle of innovation and QM together with other resources and competencies will allow organisations to obtain a competitive advantage and adapt to their environment. The results show that the factors determining innovation – such as resistance to change, cohesion and workload pressures – have repercussions for the firms’ capacity to adapt to their environmentand that a QM context facilitates this adaptation. Finally, we can conclude that a climate of support for innovation is positively related to the organisation’s performance.