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1.
It is often of interest to find the maximum or near maxima among a set of vector‐valued parameters in a statistical model; in the case of disease mapping, for example, these correspond to relative‐risk “hotspots” where public‐health intervention may be needed. The general problem is one of estimating nonlinear functions of the ensemble of relative risks, but biased estimates result if posterior means are simply substituted into these nonlinear functions. The authors obtain better estimates of extrema from a new, weighted ranks squared error loss function. The derivation of these Bayes estimators assumes a hidden‐Markov random‐field model for relative risks, and their behaviour is illustrated with real and simulated data.  相似文献   
2.
Sport for Development has many reported benefits, but quantitative evidence of the impact of these interventions in Low Income Countries remains sparse. A new monitoring and evaluation toolkit was used in a cross-sectional survey at Moving the Goalposts (MTG), a football project aiming to empower young Kenyan women. We wished to determine empirically whether increased membership duration brought increased benefits. MTG selected and translated toolkit items consistent with the organisation's strategic aims. We collected 333 completed questionnaires at 15 sites. Psychometric validation revealed some reliable scales; remaining items were scored separately. Scores were sensitive to differences between members defined by sociodemographic and site characteristics. Bivariate and multiple regression analyses showed that increased membership duration brought increasing benefits across several domains (perceived lifeskills; social life; insights about HIV/AIDS; outcomes related to female empowerment). Improved leadership skills were mainly age-related. Members attending more established sites experienced greater benefits, but members at more and less accessible sites benefitted similarly. Positive thoughts and feelings were related not to membership duration, but to how long a site had been operating. This indicates the importance of creating a positive culture over time. This cross-sectional study provides quantitative evidence for the benefits of Sport for Development initiatives.  相似文献   
3.
Lifetime Data Analysis - CD4-based multi-state back-calculation methods are key for monitoring the HIV epidemic, providing estimates of HIV incidence and diagnosis rates by disentangling their...  相似文献   
4.
This study investigated whether pupil size during the viewing of images of adults and children reflects the sexual orientation of heterosexual, homosexual, and bisexual men (n = 100, Mage = 22). More specifically, we explored whether this measure corresponds with sexual age preferences for adults over children in nonpedophilic men. In general, results across three experiments, in which observers freely viewed or rated the sexual appeal of person images, suggest that pupil dilation to sexual stimuli is an indicator of sexual orientation toward adults. Heterosexual men’s pupils dilated most strongly to adults of the other sex, homosexual men dilated most strongly to adults of the same sex, and bisexual men showed an intermediate pattern. Dilation to adults was substantially stronger than dilation to younger age groups. Sexual appeal ratings for images of adults and children also correlated with pupil responses, suggesting a direct link between pupil dilation and sexual interest. These findings provide support for pupil dilation as a measure of sex- and age-specific sexual preferences.  相似文献   
5.
Remote sensing of the earth with satellites yields datasets that can be massive in size, nonstationary in space, and non‐Gaussian in distribution. To overcome computational challenges, we use the reduced‐rank spatial random effects (SRE) model in a statistical analysis of cloud‐mask data from NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on board NASA's Terra satellite. Parameterisations of cloud processes are the biggest source of uncertainty and sensitivity in different climate models’ future projections of Earth's climate. An accurate quantification of the spatial distribution of clouds, as well as a rigorously estimated pixel‐scale clear‐sky‐probability process, is needed to establish reliable estimates of cloud‐distributional changes and trends caused by climate change. Here we give a hierarchical spatial‐statistical modelling approach for a very large spatial dataset of 2.75 million pixels, corresponding to a granule of MODIS cloud‐mask data, and we use spatial change‐of‐Support relationships to estimate cloud fraction at coarser resolutions. Our model is non‐Gaussian; it postulates a hidden process for the clear‐sky probability that makes use of the SRE model, EM‐estimation, and optimal (empirical Bayes) spatial prediction of the clear‐sky‐probability process. Measures of prediction uncertainty are also given.  相似文献   
6.
Beginning in the 1980s, Mexico's social and labour policies took a neoliberal turn which exacerbated inequalities, poverty and social exclusion. The change of policy course that has occurred over the past decade has so far failed to bring about a critical review of the country's economic model and its social consequences. The role of the State has been systematically cut back; social services have been outsourced to the market; and informal family‐based social protection has gained ground. Mexico's social model has thus been reduced to a system that is almost exclusively concerned with protection for those living in extreme poverty.  相似文献   
7.
Aggressive behavior has been well studied in terms of interindividual differences among aggressors and victims, but has been understudied, especially within naturalistic contexts, in terms of aggressor–victim relationships. The social relations model (SRM) is a powerful conceptual and analytic tool for studying dyadic phenomena, and we describe the use of multivariate SRM to study aggression. Boys and girls (N = 210) in middle schools (sixth and seventh grades) completed a newly created dyadic aggression and victimization inventory (DAVI). Results support the reliability and validity of the DAVI in assessing inter‐individual and inter‐dyadic differences in aggression and victimization. Occurrences of aggression were accounted for primarily by inter‐dyadic variability, indicating the importance of considering aggressor–victim relationships. We discuss the implications of this relationship focus for future research and intervention efforts.  相似文献   
8.
This article describes an outpatient treatment program for adolescent sexual abusers that was established by a mental health agency in collaboration with a specialized probation program in the juvenile court. Individualized treatment is based on a comprehensive clinical assessment with the youth and guardian, for which examples are provided. Given the heterogeneity of this population, we describe several treatment strategies directed to various individual or family clinical targets, including psychiatric disorders, sexual deviance and sexuality, normal adolescent development and adaptive skills, and parent and family relationships. Ongoing collaborative and coordination issues are also reviewed. The integration of mental health and probationary services provides a balanced approach to the community management and treatment of the low-risk, primarily first-time, adolescent sexual offender.  相似文献   
9.
Noel D Uri 《Omega》1977,5(4):463-472
It has recently been shown that the Box-Jenkins approach to forecasting time series is superior to an econometric approach over a relatively short horizon. The results here support this contention. A combination of the two approaches, however, proves to be clearly superior to either one separately. By taking account of changes in economic and weather related variables in a time series model, improved forecasts are obtained.  相似文献   
10.
This paper presents a review of empirical research on the impact of acquisitions on firm performance. The evidence suggests that, in the short run, acquisitions have at best an insignificant impact on shareholder wealth. Long‐run performance analysis reveals overwhelmingly negative returns, while the evidence using accounting performance measures is mixed. The review also examines the impact of bid characteristics on performance. The acquisition of hostile targets, transactions that are paid for with cash and acquisitions of larger targets are associated with superior (or at least less negative) performance, while there is mixed evidence on the benefits of related acquisitions. A number of recent studies find that acquirers with superior pre‐bid performance tend to experience significant underperformance in the post‐bid period.  相似文献   
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