Changes in risky gambling prevalence among a New Zealand population cohort

Evidence suggests that problem gambling is an unstable state where gamblers move into and out of risk over time. This article looks at longitudinal changes in risky gambling and the factors associated with an increased risk (measured by the Problem Gambling Severity Index [PGSI]) in the current New Zealand context, which has experienced a doubling of the electronic gaming machine (EGM) market over the last two decades. Respondents from a nationally representative baseline sample (n = 2672) were recontacted two years later to assess changes in gambling behaviours. Among the 901 respondents reached at follow-up, average gambling risk increased over time, and the prevalence of those who had at least some level of gambling risk (i.e. low-risk or greater) more than doubled (from 4.7% to 12.4%). The majority (80.2%) of those who were at risk at follow-up had not been at risk at baseline. Multivariate linear regression analyses show that the predictors of low to moderate increased risk include Pacific ethnicity; high neighbourhood deprivation status; baseline frequent, continuous gambler type; baseline PGSI status; and playing EGMs. These findings highlight the need to develop theories of gambling addiction trajectories and to identify the earliest point along the trajectory where public health interventions should occur.     

论我国国外马克思主义研究的三个核心问题——兼论我国国外马克思主义研究的自我身份认同

研究边界的日益模糊、研究对象选择的随意性和研究方法的非历史性,是制约我国国外马克思主义研究进一步走向深入的三大核心问题。应当对国外马克思主义研究的边界和理论性质作大致明确的规定,并且立足于推进中国马克思主义理论建设和现代化实践这一目的出发,破除形而上学的两极思维方式,展开对国外马克思主义理论的研究,实现国外马克思主义研究在当代中国的价值。     

Effective eProcurement implementation process

As eProcurement is gaining popularity in business practice, researchers as well as practitioners have addressed the need of defining a proper eProcurement implementation strategy. This article aims to build an eProcurement implementation framework, which considers the main variables that have an impact on the eProcurement success and the links among them. The goal is to identify the main decisions that companies should take during the three principal phases of the eProcurement adoption (pre-implementation; implementation and post-implementation). Six case studies at different levels of eProcurement adoption have been used to identify the peculiarities of each phase of the process and to provide contingent guidelines.     

Marginal homogeneity,symmetry, and independence

A contingency table of the mc form provides a convenient summary of data when c individuals in a matched set9 each belonging to a different one of c classifications, are identified as belonging to one of m categories, A study in which matched sets (c=3) of 1 case, 1 hospital control, and 1 neighborhood control are classified into one of m=4 occupational categories would be an example, Independence in the cxm tables for each of the matched sets implies symmetry in the summary mc table with consequent marginal homogeneity. Adaptation of the Mantel-Haenszel procedure for testing independence to the case of many cxm tables so as to yield a chi square with (cl)(ml) degrees of freedom (DF) provides a test of marginal homogeneity in the summary mc table. This can be viewed as a test of symmetry directed against alternatives which would make for marginal inhomogeneity and can differ     

民族社会学视野下的回族女性研究

回族女性研究是中国妇女研究的重要组成部分,20世纪90年代以来,中国回族女性研究取得了长足的进步和发展。本文着力于回顾既往回族女性研究中所涉及的诸多问题展开历史追溯与反思,就回族女性研究的内涵、研究的对象与范围、研究的意义与作用、研究的方法、理论构建、学术素养等学术界较为关注的几个问题进行了论述,在追溯中反思我们今后研究的拓展方向,力求为未来回族女性的发展提供一定参考。     

近十年来土族研究综述

本文从历史、语言文字、文学艺术、宗教文化、婚姻家庭、经济发展等方面 ,对土族近十年来的研究状况作了总结 ,可资参考     

北亚突厥百年研究(1900-2000年)

突厥是生活在我国北方的一个游牧民族。其在公元六世纪中叶,兴起于今新疆东北部,势力扩大到漠北、漠南及中亚一带,衰于八世纪中叶。本文综述阿尔泰以东的突厥即传统上所说的东突厥的范围近百余年的研究。包括族源、族属、社会性质、社会经济、语言、文字、习俗、宗教、碑文、官号、与周边各族各国间的关系和其他方面的内容。通过这些研究,可以发现我国学者在百年来对突厥巨大成就,使国际学术同行了解我国学者在这一领域取得的成果,促进此方面的进一步研究。该文可能对方家一些著述有遗漏,或者评述失当之处,请予指教。     

Mixed-effects Models with Skewed Distributions for Time-varying Decay Rate in HIV Dynamics

After initiation of treatment, HIV viral load has multiphasic changes, which indicates that the viral decay rate is a time-varying process. Mixed-effects models with different time-varying decay rate functions have been proposed in literature. However, there are two unresolved critical issues: (i) it is not clear which model is more appropriate for practical use, and (ii) the model random errors are commonly assumed to follow a normal distribution, which may be unrealistic and can obscure important features of within- and among-subject variations. Because asymmetry of HIV viral load data is still noticeable even after transformation, it is important to use a more general distribution family that enables the unrealistic normal assumption to be relaxed. We developed skew-elliptical (SE) Bayesian mixed-effects models by considering the model random errors to have an SE distribution. We compared the performance among five SE models that have different time-varying decay rate functions. For each model, we also contrasted the performance under different model random error assumptions such as normal, Student-t, skew-normal, or skew-t distribution. Two AIDS clinical trial datasets were used to illustrate the proposed models and methods. The results indicate that the model with a time-varying viral decay rate that has two exponential components is preferred. Among the four distribution assumptions, the skew-t and skew-normal models provided better fitting to the data than normal or Student-t model, suggesting that it is important to assume a model with a skewed distribution in order to achieve reasonable results when the data exhibit skewness.     

Investigating impacts of complex sampling on latent growth curve modelling

We investigate the impacts of complex sampling on point and standard error estimates in latent growth curve modelling of survey data. Methodological issues are illustrated with empirical evidence from the analysis of longitudinal data on life satisfaction trajectories using data from the British Household Panel Survey, a national representative survey in Great Britain. A multi-process second-order latent growth curve model with conditional linear growth is used to study variation in the two perceived life satisfaction latent factors considered. The benefits of accounting for the complex survey design are considered, including obtaining unbiased both point and standard error estimates, and therefore correctly specified confidence intervals and statistical tests. We conclude that, even for the rather elaborated longitudinal data models that were considered, estimation procedures are affected by variance-inflating impacts of complex sampling.     

Goodness-of-fit tests of generalized linear mixed models for repeated ordinal responses

Categorical longitudinal data are frequently applied in a variety of fields, and are commonly fitted by generalized linear mixed models (GLMMs) and generalized estimating equations models. The cumulative logit is one of the useful link functions to deal with the problem involving repeated ordinal responses. To check the adequacy of the GLMMs with cumulative logit link function, two goodness-of-fit tests constructed by the unweighted sum of squared model residuals using numerical integration and bootstrap resampling technique are proposed. The empirical type I error rates and powers of the proposed tests are examined by simulation studies. The ordinal longitudinal studies are utilized to illustrate the application of the two proposed tests.