Spectral goodness of fit for network models

We introduce a new statistic, ‘spectral goodness of fit’ (SGOF) to measure how well a network model explains the structure of the pattern of ties in an observed network. SGOF provides a measure of fit analogous to the standard R² in linear regression. Additionally, as it takes advantage of the properties of the spectrum of the graph Laplacian, it is suitable for comparing network models of diverse functional forms, including both fitted statistical models and algorithmic generative models of networks. After introducing, defining, and providing guidance for interpreting SGOF, we illustrate the properties of the statistic with a number of examples and comparisons to existing techniques. We show that such a spectral approach to assessing model fit fills gaps left by earlier methods and can be widely applied.     

The future of PR is ‘fantastic’, ‘friendly’ and ‘funny’: Occupational stereotypes and symbolic capital in entry-level job advertisements

Over the past decade, there has been a move towards examining public relations as a socio-cultural practice, acknowledging practitioners as influential communicators who produce and symbolise cultural values through public relations messages. Ideally, a diverse group of professionals would aide in representing a diverse society, but to date, the profession remains female dominated. In this article, it is proposed that practitioners’ own discourse do not only establish what is most valued in the occupation and which habitus suits the practice best, but that the discourse also opens and closes occupational entry for new practitioners thereby contributing to a lack of diversity.This article presents the findings of an indicative thematic content analysis of one of the most common, yet under-research sites of discourse, namely entry-level job advertisements in New Zealand and Australia. Using an interdisciplinary approach, the analysis found that the advertisements placed little to no emphasis on the nature of the work, instead focusing on elements of ‘fit’ whereby new entrants were expected to be charismatic, friendly, and willing to work in an environment that is ‘fun’ and ‘flexible’. In doing so, public relations practitioners tacitly created invisible barriers, a self-limiting occupational culture and furthered existing stereotypes of the ‘perfect’ practitioner.     

Likelihood ratio tests for multivariate normality

This paper presents some powerful omnibus tests for multivariate normality based on the likelihood ratio and the characterizations of the multivariate normal distribution. The power of the proposed tests is studied against various alternatives via Monte Carlo simulations. Simulation studies show our tests compare well with other powerful tests including multivariate versions of the Shapiro–Wilk test and the Anderson–Darling test.     

Europeanisation and the Youth Guarantee: The case of France

In 2013, the European Council approved the Youth Guarantee (YG) to counteract youth unemployment. Because of its specific features, the YG is useful for understanding whether the EU has triggered policy change in national youth unemployment policies. Contrary to most of the literature on similar topics, we focused in this study on the effect of this specific European measure rather than on broader EU strategies or policies. The study contributes to the literature by qualifying the degree of fit/misfit and suggesting a counterfactual analysis, using the case of France. We first situate the article within the broader Europeanisation debate and present our research design. The second section introduces the policy structure of the YG and investigates youth unemployment policy in France, prior to and after the European initiative. The third section discusses whether the French youth unemployment policy would have been developed in the same way without the YG. A final section concludes.     

让农村籍员工自愿留在企业中:内部营销作用于留任意愿的机理研究

通过理清内部营销作用于留任意愿的机理, 找出让农村籍员工自愿留在企业中的途径。收集701份针对农村籍员工的有效问卷调查数据, 采用SPSS 21与LISREL 8.70进行统计分析。研究结果表明:内部营销对留任意愿有显著的正向影响, 组织认同在其中起到部分中介的作用。个体-组织匹配程度的不同还会严重影响到内部营销对留任意愿作用的强度以及员工“是走是留”。     

A new estimator of Kullback–Leibler information and its application in goodness of fit tests*

We propose here a general statistic for the goodness of fit test of statistical distributions. The proposed statistic is constructed based on an estimate of Kullback–Leibler information. The proposed test is consistent and the limiting distribution of the test statistic is derived. Then, the established results are used to introduce goodness of fit tests for the normal, exponential, Laplace and Weibull distributions. A simulation study is carried out for examining the power of the proposed test and to compare it with those of some existing procedures. Finally, some illustrative examples are presented and analysed, and concluding comments are made.     

Semi-doubly optimal concentric circles fitting with presence of heteroscedasticity

Previous studies focus on homogeneous and isotropic assumptions about the noisy data. Many methods have been developed recently for fitting concentric circles to data. In this paper, these statistical assumptions have been relaxed. To the best of our knowledge, only one iterative method has been recently developed. Due to its complexity, no such algorithm is available to compute the reliable maximum likelihood estimator (MLE). Accordingly, we have developed four new methods that outperform the existing methods including the orthogonal distance regression (ODR). We also discuss which of these methods is superior according to the four principles: statistical efficiency, accuracy, robustness, and computational efficiency. Numerical experiments on synthetic and real images have been conducted to validate our findings.     

Model Checks in Inverse Regression Models with Convolution‐Type Operators

Abstract. We consider the problem of testing parametric assumptions in an inverse regression model with a convolution‐type operator. An L ₂ ‐type goodness‐of‐fit test is proposed which compares the distance between a parametric and a non‐parametric estimate of the regression function. Asymptotic normality of the corresponding test statistic is shown under the null hypothesis and under a general non‐parametric alternative with different rates of convergence in both cases. The feasibility of the proposed test is demonstrated by means of a small simulation study. In particular, the power of the test against certain types of alternative is investigated. Finally, an empirical example is provided, in which the proposed methods are applied to the determination of the shape of the luminosity profile of the elliptical galaxy NGC 5017.     

Complementary person-supervisor fit: An investigation of supplies-values (S-V) fit,leader-member exchange (LMX) and work outcomes

By applying the supplies-values (S-V) fit approach from the complementary person-environment (P-E) fit literature to the leader-employee perspective, and drawing upon social exchange theory, we examine how fulfillment of different work values is related to Leader-Member Exchange (LMX) and work outcomes. First, polynomial regression analyses combined with response surface analysis of data collected at two time points (N = 316) showed that LMX (Time 2) was higher the more the leader fulfills the employee's work values (Time 1). Second, LMX (Time 2) was higher when leader supplies (Time 1) and employee work values (Time 1) were both high than when both were low. Third, analyses of data from a sub-sample of matched leader-employee dyads (N = 140), showed that LMX (Time 2) played a mediating role on the relation between S-V fit (Time 1) and work outcomes (Time 2). Specifically, we found eight out of 10 relationships between S-V fit (Time 1) and leader-rated task performance and OCB (Time 2) to be fully mediated by LMX (Time 2). LMX (Time 2) partially mediated the relation between S-V fit (Time 1) and job satisfaction (Time 2) as only two out of five relationships were fully mediated.