The prevalence of problem and pathological gambling: A critical analysis

Prevalence of pathological gambling refers to the percentage of cases of pathological gambling occurring in the community at a given time. Prevalence studies conducted in different principalities throughout the world are reviewed, and it is found that none of them conforms to this definition of prevalence. The major error in all but the most recent surveys conducted is identified as the use of questions which ask whether gambling-related problems have ever occurred rather than whether they are currently occurring. This error will lead to an over-estimation of the prevalence of pathological gambling in society. The second major error identified in nearly all studies involves the accuracy of the screens being used to assess whether or not an individual is a pathological gambler. Concerns about the efficiency of the South Oaks Gambling Screen have not yet been satisfactorily resolved. None-the-less, the widespread use of the South Oaks Gambling Screen has made a valuable contribution to international comparisons of prevalence studies. Future work that explores the emerging relationship between levels of personal expenditure on gambling, types of gambling product and gambling-related problems are recommended.     

Productivity indices and survival rate estimates from MAPS,a continent-wide programme of constant-effort mist-netting in North America

The Monitoring Avian Productivity and Survivorship (MAPS) programme is a cooperative effort to provide annual regional indices of adult population size and post-fledging productivity and estimates of adult survival rates from data pooled from a network of constant-effort mist-netting stations across North America. This paper provides an overview of the field and analytical methods currently employed by MAPS, a discussion of the assumptions underlying the use of these techniques, and a discussion of the validity of some of these assumptions based on data gathered during the first 5 years (1989-1993) of the programme, during which time it grew from 17 to 227 stations. Ageand species-specific differences in dispersal characteristics are important factors affecting the usefulness of the indices of adult population size and productivity derived from MAPS data. The presence of transients, heterogeneous capture probabilities among stations, and the large sample sizes required by models to deal effectively with these two considerations are important factors affecting the accuracy and precision of survival rate estimates derived from MAPS data. Important results from the first 5 years of MAPS are: (1) indices of adult population size derived from MAPS mist-netting data correlated well with analogous indices derived from point-count data collected at MAPS stations; (2) annual changes in productivity indices generated by MAPS were similar to analogous changes documented by direct nest monitoring and were generally as expected when compared to annual changes in weather during the breeding season; and (3) a model using between-year recaptures in Cormack-Jolly-Seber (CJS) mark-recapture analyses to estimate the proportion of residents among unmarked birds was found, for most tropical-wintering species sampled, to provide a better fit with the available data and more realistic and precise estimates of annual survival rates of resident birds than did standard CJS mark-recapture analyses. A detailed review of the statistical characteristics of MAPS data and a thorough evaluation of the field and analytical methods used in the MAPS programme are currently under way.     

Unintended Consequences of Land Rights Reform: The Case of the 1998 Uganda Land Act

Empirical studies of land rights privatisation have tended to underemphasise the unintended impacts of land rights reform relative to establishing whether the predicted impacts have occurred. This article, in reviewing some of the unintended consequences of the 1998 Uganda Land Act, draws attention to ways in which intended impacts may be undercut by lack of both consultation and foresight in anticipating responses to new legal provisions and by lack of adequate resourcing of the reform process. It also recognises that unintended outcomes may sometimes reflect appropriate adaptations of legal provisions at the local level, and briefly considers what light the Ugandan experience can throw on recent proposals for Normalisation of informal property rights in the Third World.     

The Differential Effects of Transformational Leadership on Multiple Identifications at Work: A Meta‐analytic Model

Employees’ identifications are a valuable asset for modern organizations, and identification research has stressed the necessity to distinguish identifications according to their focus (i.e. organizational, team, or leader identification). Interestingly, transformational leadership (TFL) has been proposed to unfold its effects by transforming followers’ identifications and could thus be a powerful way to actively manage identification. However, it remains unclear whether TFL affects identifications with different foci similarly or whether it predominantly influences a specific focus. To resolve this puzzle, the authors conducted a meta‐analysis (k = 73; N = 20,543) and found that TFL (and each TFL sub‐dimension) is more strongly associated with leader identification than with organizational identification or team identification. By presenting a comprehensive model of TFL's effects on identifications, we show that leader identification mediates the relationships between TFL and collective identifications (i.e. organizational identification or team identification), illustrating that relational identification plays a crucial role in subsequently shaping collective identifications. Implications for research and practice are discussed.     

How Leaders Affect Followers’ Work Engagement and Performance: Integrating Leader−Member Exchange and Crossover Theory

Drawing on leader?member exchange and crossover theory, this study examines how leaders’ work engagement can spread to followers, highlighting the role of leader?member exchange as an underlying explanatory process. Specifically, we investigate if leaders who are highly engaged in their work have better relationships with their followers, which in turn can explain elevated employee engagement. For this purpose, we surveyed 511 employees nested in 88 teams and their team leaders in a large service organization. Employees and supervisors provided data in this multi‐source design. Furthermore, we asked the employees to report their annual performance assessment. We tested our model using multilevel path analyses in Mplus. As hypothesized, leaders’ work engagement enhanced leader?member exchange quality, which in turn boosted employee engagement (mediation model). Moreover, employee engagement was positively linked to performance and negatively linked to turnover intentions. As such, our multilevel field study connects the dots between work engagement research and the leadership literature. We identify leaders’ work engagement as a key to positive leader?follower relationships and a means for promoting employee engagement and performance. Promoting work engagement at the managerial level may be a fruitful starting point for fostering an organizational culture of engagement.     

Climate change knowledge influences attitude to mitigation via efficacy beliefs

Theories proposing climate change apathy is explained by inadequate knowledge do not account for why many informed and concerned Americans fail to act. While correlations between knowledge, efficacy for climate change, and attitude to mitigation have been observed, few studies have examined efficacy for climate change as a mediator. This study aimed to investigate the influence of specific climate change knowledge on attitude to mitigation via efficacy beliefs. A cross-sectional survey of 205 US adults recruited from Amazon's Mechanical Turk assessed participants’ climate change knowledge, efficacy for climate change, and attitude to mitigation. Indirect effects of self-efficacy for climate change were observed in three mediation models, suggesting efficacy for climate change explains some of the relationship between specific climate change knowledge and attitude to mitigation. The findings suggest risk communication can motivate pro-environmental attitudes with interventions that deliver information about climate change and develop efficacy for mitigation behavior.     

Social Trust and E-Commerce: Experimental Evidence for the Effects of Social Trust on Individuals' Economic Behavior

In this study, an experimental design embedded in a nationalsurvey is used to examine the impact of social trust on participationin e-commerce. To what extent does generalized trust in peopleinfluence economic behavior, particularly in newly establishedrealms such as the Internet? Although some previous work hasposited a role for social trust in encouraging both e-commerceand economic development more generally, evidence has been basedon cross-sectional associations and, primarily, at the aggregatelevel of entire countries. While these relationships have beensuggestive, studies have yet to confirm a causal role for socialtrust in influencing e-commerce. Would increasing levels ofsocial trust actually encourage greater e-commerce participation?This study combines the representativeness of a national surveywith the internal validity of an experimental design to answerthis question.     

Bivariate modelling of longitudinal measurements of two human immunodeficiency type 1 disease progression markers in the presence of informative drop-outs

Summary.  The main statistical problem in many epidemiological studies which involve repeated measurements of surrogate markers is the frequent occurrence of missing data. Standard likelihood-based approaches like the linear random-effects model fail to give unbiased estimates when data are non-ignorably missing. In human immunodeficiency virus (HIV) type 1 infection, two markers which have been widely used to track progression of the disease are CD4 cell counts and HIV–ribonucleic acid (RNA) viral load levels. Repeated measurements of these markers tend to be informatively censored, which is a special case of non-ignorable missingness. In such cases, we need to apply methods that jointly model the observed data and the missingness process. Despite their high correlation, longitudinal data of these markers have been analysed independently by using mainly random-effects models. Touloumi and co-workers have proposed a model termed the joint multivariate random-effects model which combines a linear random-effects model for the underlying pattern of the marker with a log-normal survival model for the drop-out process. We extend the joint multivariate random-effects model to model simultaneously the CD4 cell and viral load data while adjusting for informative drop-outs due to disease progression or death. Estimates of all the model's parameters are obtained by using the restricted iterative generalized least squares method or a modified version of it using the EM algorithm as a nested algorithm in the case of censored survival data taking also into account non-linearity in the HIV–RNA trend. The method proposed is evaluated and compared with simpler approaches in a simulation study. Finally the method is applied to a subset of the data from the 'Concerted action on seroconversion to AIDS and death in Europe' study.     

创新行为如何影响政府绩效:以领导干部任前公示为例的研究探索

在以往关注不同类型创新行为对组织绩效影响的研究中,组织氛围与沟通、人力资源与管理和行政成本是三类较为常见的影响因素,但三者尚未综合形成统一的框架。本研究选取了领导干部任前公示这一以人力资源管理为内容的创新行为,构建了三因素影响组织绩效的过程假设。通过分析问卷调查数据,发现三因素之间存在显著的相关性,且若按照组织边界划分绩效内容,三因素均与组织的内部成长建设绩效显著相关,而同组织外部绩效水平相关程度较弱。依此认为,创新行为影响绩效是一个由人、财、物三因素互动,并依据创新本身特点内容有所侧重的过程。