Testing the equality of matrix distributions

Statistical Methods & Applications - While matrices are usually used as the basic data structure for experiments with repeated measurements or longitudinal data, testing methods for the...     

A flexible generalization of the skew normal distribution based on a weighted normal distribution

The skew normal distribution of Azzalini (Scand J Stat 12:171–178, 1985) has been found suitable for unimodal density but with some skewness present. Through this article, we introduce a flexible extension of the Azzalini (Scand J Stat 12:171–178, 1985) skew normal distribution based on a symmetric component normal distribution (Gui et al. in J Stat Theory Appl 12(1):55–66, 2013). The proposed model can efficiently capture the bimodality, skewness and kurtosis criteria and heavy-tail property. The paper presents various basic properties of this family of distributions and provides two stochastic representations which are useful for obtaining theoretical properties and to simulate from the distribution. Further, maximum likelihood estimation of the parameters is studied numerically by simulation and the distribution is investigated by carrying out comparative fitting of three real datasets.     

On comparing,classifying and clustering several dependent regression models

Classifying several regression models fitted on a dataset is one of the most problems in data analysis. In other words, scientists are interested in comparing several regression models that can be used for a dataset. In this paper, an approach will be used to compare and classify several dependent regression models. Then the performance of the proposed method is investigated using simulation study and real example.     

Professors,Ideology and Housework

This paper presents, for the first time, multivariate analyses of Canadian national data and tests the relationship between class-based egalitarianism and housework for married and cohabiting male and female university professors in 2000. Consistent with evidence in the general population, gender accounts for more variation in housework than a host of other predictors (i.e., class- and gender-based ideology, institutional contexts and resources, available time, presence of children, age, minority racial status, and religiosity). Nevertheless, these forces play important roles in increasing or decreasing domestic labor contributions of both male and female academics. Among these, professors who possess class-based egalitarian views do more housework, and egalitarianism increases domestic labor contributions of males and decreases that of females.     

NGO Strategies in an Authoritarian Context,and Their Implications for Citizenship: The Case of the People’s Republic of China

This study argues that different cities in China have different resource environments available for NGOs. Organizations react to these resource environments by constructing appropriate resource strategies, which in turn shape the characteristics and structures of the NGOs of that city. It further examines how these characteristics and structures influence the construction and performance of citizenship in an authoritarian environment. Specifically, some types of NGOs encourage Chinese citizens to be passive, while others offer a model for people to actively engage with social issues. This is aptly demonstrated in an analysis of NGOs operating across four cities—Beijing, Shanghai, Kunming, and Nanjing—which reveals three different types of resource environments and behavioral models for NGOs. We subsequently discuss the implications of each model for citizen engagement.     

The discrepancy of P-values and posterior probability: Two-sided hypothesis of variance of normal distribution with unknown mean

This article is concerned with the comparison of P-value and Bayesian measure in point null hypothesis for the variance of Normal distribution with unknown mean. First, using fixed prior for test parameter, the posterior probability is obtained and compared with the P-value when an appropriate prior is used for the mean parameter. In the second, lower bounds of the posterior probability of H₀ under a reasonable class of prior are compared with the P-value. It has been shown that even in the presence of nuisance parameters, these two approaches can lead to different results in the statistical inference.     

The competing risks analysis for parallel and series systems using Type-II progressive censoring

Abstract

Recently, the study of the lifetime of systems in reliability and survival analysis in the presence of several causes of failure (competing risks) has attracted attention in the literature. In this paper, series and parallel systems with exponential lifetime for each item of the system are considered. Several causes of failure independently affect lifetime distributions and observations of failure times of the systems are considered under progressive Type-II censored scheme. For series systems, the maximum likelihood estimates of parameters are computed and confidence intervals for parameters of the model are obtained using Fisher information matrix. For parallel systems, the generalized EM algorithm which uses the Newton-Raphson algorithm inside the EM algorithm is used to compute the maximum likelihood estimates of parameters. Also, the standard errors of the maximum likelihood estimates are computed by using the supplemented EM algorithm. The simulation study confirms the good performance of the introduced approach.     

Effect of Sociocultural Context and Parenting Style on Scholastic Achievement among Iranian Adolescents

School grades, family demographics and responses to the parental authority questionnaire were assessed in 240 eighth‐grade students in the southern, central and northern parts of Tehran, Iran's capital. The result showed that poorer families with traditional values had more authoritarian attitudes toward parenting than richer families with more modern values. In contrast to the studies conducted in East Asian societies, the current study found that authoritative parenting was the style associated with the highest academic outcome. Tests of mediation and moderation effects showed that the relation between parenting style and academic outcome was independent of sociocultural context.