Generalizing the Welch Test To Non-Zero Hypotheses on the Variance Component in the One-Way Random Effects Model Under Variance Heterogeneity

In an unbalanced and heteroscedastic one-way random effects model of analysis of variance we consider hypotheses concerning the between group variance where in a classical set-up the hypothesis whether this variance component is zero is tested. We consider the still open problem of testing also extended hypotheses concerning this parameter and generalize the prominent Welch test to deal with these hypotheses, too.     

Bayesian inference for comparing two Poisson rates using data subject to underreporting and validation data

We derive a new Bayesian credible interval estimator for comparing two Poisson rates when counts are underreported and an additional validation data set is available. We provide a closed-form posterior density for the difference between the two rates that yields insightful information on which prior parameters influence the posterior the most. We also apply the new interval estimator to a real-data example, investigate the performance of the credible interval, and examine the impact of informative priors on the rate difference posterior via Monte Carlo simulations.     

Who Plays What? Participation Profiles in Chance Versus Skill-based Gambling

To determine whether gambling participation falls into skill and chance-based categories and, if so, to determine the socio-demographic characteristics associated with these different categories. A cross-sectional analysis of all respondents to the 2005 Northern Territory Gambling Prevalence Survey who gambled in the 12 months prior to the survey. Factor analysis was employed to determine whether a chance versus skill-based dichotomy described the structure of gambling participation. Gambler preference groups were constructed using the median of rotated factor scores. Multinomial logit regression was then used to determine independent associations between explanatory variables and categories of gambler preferences. The skill and chance-based dichotomy did describe player preferences for the sample of adult gamblers in the Northern Territory, Australia. Gender, age, household income, household structure and the geographic location (access to gambling opportunities) of respondents were all associated with different degrees of participation in skill and chance based gambling activities. Notably, respondents 35 years and over were significantly over-represented in the low-skill/high-chance participation group, and under-represented in the high-skill/low-chance group. It is clear that the term gambling is a confounding rubric that hides differences both in the type of activity and the socio-demographic profiles of participants. An examination of the latter raises important questions about the role of chance in later life, as well as the role of self-determination in gambling for other groups, particularly younger men.     

Contests with group-specific public-good prizes

We examine the equilibrium effort levels of individual players and groups in contests in which n groups compete to win a group-specific public-good prize, the individual players choose their effort levels simultaneously and independently, and the probability of winning for each group depends on the groups’ effort levels. In the basic model, we show that, in each group, only the highest-valuation players expend positive effort and the rest expend zero effort; there is underinvestment in the contest for the group as a whole. Next, in the main model in which the players are budget-constrained, we show that low-valuation players free ride on high-valuation players’ contributions, not vice versa, but the free-rider problem is “alleviated” as compared with the basic model.     

Effects of Parent Effectiveness Training Program on Family Communication and Flexibility of Korean Parents

This study examines the effects of an 8‐week Parent Effective Training (PET) program on family communication and flexibility. Forty‐two pairs of Korean parents were randomly assigned to either an experimental group that provided the PET program or a control group that did not offer the program. The two groups were compared on pre‐, post‐, and follow‐up measures of PAC(Parent‐Adolescent Communication), ENRICH(Enriching and Nurturing Relationship Issues, Communication and Happiness), and FACES(Family Adaptability Cohesion Evaluation Scale), while controlling for the effects of socio‐demographic variables. Compared with the control group, the experimental group showed significant improvements in family communication between parents and children and between the husband and the wife but no such improvements in family flexibility. These findings suggest that the PET program is a useful short‐term tool for Korean parents wishing to enhance family communication.     

The power of the exponential scores test for an ordinary renewal process against trend alternatives

The power properties of a statistic based on the use of exponential scores which may be used for testing whether a series of events occurring in time form an ordinary renewal process against trend alternatives are examined. Small sample power comparisons under a Lehmann trend alternative are made with an alternative nonparametric test based on a rank trend statistic and with the parametric test when the intervals are exponentially distributed. Finally, some asymptotic efficiency results are developed for limiting trend alternatives.     

The Roles of Worker Expertise,Information Sharing Quality,and Psychological Safety in Manufacturing Process Innovation: An Intellectual Capital Perspective

This paper examines the roles of three elements of intellectual capital in implementing process innovations. Building upon prior literature, we develop a model describing how worker expertise, information sharing quality, and psychological safety work together as elements of the human, structural, and social dimensions of intellectual capital to influence the technical success of manufacturing process innovation (MPI) projects. Results of an analysis of data describing 179 MPI projects in US firms strongly support a multidimensional, process‐oriented view of intellectual capital's effects on MPI project technical performance. We also find that the incrementalness of an MPI project plays a moderating role over the relationship between worker expertise and MPI performance. Our study provides insights on how intellectual capital can be more effectively accumulated in a project environment.     

Institutions and the gender wage gap: How production and welfare regime moderates the effect of family policy

The aim of this study was to determine whether the effects of work and family reconciliation policy on the gender wage gap are moderated by institutional contexts of production and welfare regime. Using time‐series analysis for 13 countries from 1981 to 2015, the study revealed a strong association between childcare and a lower gender wage gap in the Coordinated Market Economies (CMEs)/social democratic welfare states but not in Liberal Market Economies (LMEs)/liberal welfare states. The study also found that the impact of leave generosity on the gender wage gap in CMEs/social democratic welfare states is less salient than in CMEs/continental welfare states. This study highlights the extent to which family policy affects the gender wage gap hinges on how each country organises its market coordination and welfare institutions and pushes the current literature forward to a question of ‘what kinds of’ family policy matters in ‘which’ production and welfare regimes.     

A comparison of regularization methods applied to the linear discriminant function with high-dimensional microarray data

Classification of gene expression microarray data is important in the diagnosis of diseases such as cancer, but often the analysis of microarray data presents difficult challenges because the gene expression dimension is typically much larger than the sample size. Consequently, classification methods for microarray data often rely on regularization techniques to stabilize the classifier for improved classification performance. In particular, numerous regularization techniques, such as covariance-matrix regularization, are available, which, in practice, lead to a difficult choice of regularization methods. In this paper, we compare the classification performance of five covariance-matrix regularization methods applied to the linear discriminant function using two simulated high-dimensional data sets and five well-known, high-dimensional microarray data sets. In our simulation study, we found the minimum distance empirical Bayes method reported in Srivastava and Kubokawa [Comparison of discrimination methods for high dimensional data, J. Japan Statist. Soc. 37(1) (2007), pp. 123–134], and the new linear discriminant analysis reported in Thomaz, Kitani, and Gillies [A Maximum Uncertainty LDA-based approach for Limited Sample Size problems – with application to Face Recognition, J. Braz. Comput. Soc. 12(1) (2006), pp. 1–12], to perform consistently well and often outperform three other prominent regularization methods. Finally, we conclude with some recommendations for practitioners.