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General Test (general + test)
Selected AbstractsThe Effect of Computer-Based Tests on Racial-Ethnic and Gender GroupsJOURNAL OF EDUCATIONAL MEASUREMENT, Issue 2 2002Ann Gallagher In this study data were examined from several national testing programs to determine whether the change from paper-based administration to computer-based tests (CBTs) influences group differences in performance. Performances by gender, racial, and ethnic groups on the Graduate Record Examination General Test, Graduate Management Admissions Test, SAT I: Reasoning Test, and Praxis: Professional Assessment for Beginning Teachers, were analyzed to determine whether the shift in testing format from paper-and-pencil tests to CBTs posed a disadvantage to any of these subgroups, beyond that already identified for paper-based tests. Although all differences were quite small, some consistent patterns were found for some racial-ethnic and gender groups. African-American examinees and, to a lesser degree, Hispanic examinees appear to benefit from the CBT format. On some tests, female examinees' performance was relatively lower on the CBT version. [source] Testing the energetic equivalence rule with helminth endoparasites of vertebratesECOLOGY LETTERS, Issue 7 2004Mario George-Nascimento Abstract As a general test of the energetic equivalence rule, we examined macroecological relationships among abundance, density and host body mass in a comparative analysis of the assemblages of trophically transmitted endoparasitic helminths of 131 species of vertebrate hosts. Both the numbers and total volume of parasites per gram of host decreased allometrically with host body mass, with slopes roughly consistent with those expected from the allometric relationship between host basal metabolic rate and body mass. From an evolutionary perspective, large body size may therefore allow hosts to escape from the deleterious effects of parasitism. [source] Tail-dependence in stock-return pairsINTELLIGENT SYSTEMS IN ACCOUNTING, FINANCE & MANAGEMENT, Issue 2 2002Ines Fortin The empirical joint distribution of return pairs on stock indices displays high tail-dependence in the lower tail and low tail-dependence in the upper tail. The presence of tail-dependence is not compatible with the assumption of (conditional) joint normality. The presence of asymmetric tail-dependence is not compatible with the assumption of a joint student-t distribution. A general test for one dependence structure versus another via the profile likelihood is described and employed in a bivariate GARCH model, where the joint distribution of the disturbances is split into its marginals and its copula. The copula used in the paper is such that it allows for the existence of lower tail-dependence and for asymmetric tail-dependence, and is such that it encompasses the normal or t-copula, depending on the benchmark tested. The model is estimated using bivariate data on a set of European stock indices. We find that the assumption of normal or student-t dependence is easily rejected in favour of an asymmetrically tail-dependent distribution. Copyright © 2002 John Wiley & Sons, Ltd. [source] THE ECONOMIC IMPACTS OF VOLUNTARY ENVIRONMENTAL PERFORMANCE OF FIRMS: A CRITICAL REVIEWJOURNAL OF ECONOMIC SURVEYS, Issue 3 2009Esther Blanco Abstract New trends in studies on the governance of natural assets include substantial consideration of the role of voluntary initiatives. A traditional economic view states that there is a trade-off between being green and being competitive. According to that view, no voluntary environmental action is expected to occur. To undertake an in-depth analysis of the scope for voluntary action, this paper reviews empirical literature that analyzes the relationship between manufacturing firms' environmental initiatives or performance and economic results. This review moves beyond the general test of the ,pay to be green' hypothesis, preferring instead to systematize empirical results in more specific research questions. Empirical findings of the reviewed literature generally support that there is no penalty for being green. In addition, the typology of firms, the methods utilized for implementing environmental initiatives, the intensity of abatement efforts and stockholders' valuation of green firms have all been shown to have a sizeable influence on the actual economic results of environmental action or management. Consequently, the findings of this paper challenge the traditional strategic theory that predicts widespread free-riding; it holds major implications for environmental policy-making and environmental business decisions. [source] Score tests for heterogeneity and overdispersion in zero-inflated Poisson and binomial regression modelsTHE CANADIAN JOURNAL OF STATISTICS, Issue 3 2002Daniel B. Hall Abstract Hall (2000) has described zero-inflated Poisson and binomial regression models that include random effects to account for excess zeros and additional sources of heterogeneity in the data. The authors of the present paper propose a general score test for the null hypothesis that variance components associated with these random effects are zero. For a zero-inflated Poisson model with random intercept, the new test reduces to an alternative to the overdispersion test of Ridout, Demério & Hinde (2001). The authors also examine their general test in the special case of the zero-inflated binomial model with random intercept and propose an overdispersion test in that context which is based on a beta-binomial alternative. Tests scores d'hétérogénéité et de surdispersion dans des modéles de régression binomiaux et de Poisson avec surplus de zéros Hall (2000) a décrit des modèles de régression binomiaux et de Poisson dans lesquels des effets aléatoires servent à expliquer certaines sources d' hétérogénéité dans les données, dont un surplus de zéros. Les auteurs du présent article proposent un test score général permettant de vérifier si les composantes de la variance associées à ces effets aléatoires sont nulles. Pour un modèle de Poisson à surplus de zéros et à ordonnée aléatoire, le nouveau test se compare au test de surdispersion de Ridout, Demétrio & Hinde (2001). Les auteurs étudient en outre leur test général dans le cadre du modèle binomial à surplus de zéros et à ordonnée aléatoire, pour lequel ils proposent un test de surdispersion adapté à des contre-hypothèses de type b,ta-binomial. [source] Antimalarial drug quality in AfricaJOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 5 2007A. A. Amin PhD Abstract Background and objective: There are several reports of sub-standard and counterfeit antimalarial drugs circulating in the markets of developing countries; we aimed to review the literature for the African continent. Methods: A search was conducted in PubMed in English using the medical subject headings (MeSH) terms: ,Antimalarials/analysis'[MeSH] OR ,Antimalarials/standards'[MeSH] AND ,Africa'[MeSH]' to include articles published up to and including 26 February 2007. Data were augmented with reports on the quality of antimalarial drugs in Africa obtained from colleagues in the World Health Organization. We summarized the data under the following themes: content and dissolution; relative bioavailability of antimalarial products; antimalarial stability and shelf life; general tests on pharmaceutical dosage forms; and the presence of degradation or unidentifiable impurities in formulations. Results and discussion: The search yielded 21 relevant peer-reviewed articles and three reports on the quality of antimalarial drugs in Africa. The literature was varied in the quality and breadth of data presented, with most bioavailability studies poorly designed and executed. The review highlights the common finding in drug quality studies that (i) most antimalarial products pass the basic tests for pharmaceutical dosage forms, such as the uniformity of weight for tablets, (ii) most antimalarial drugs pass the content test and (iii) in vitro product dissolution is the main problem area where most drugs fail to meet required pharmacopoeial specifications, especially with regard to sulfadoxine,pyrimethamine products. In addition, there are worryingly high quality failure rates for artemisinin monotherapies such as dihydroartemisinin (DHA); for instance all five DHA sampled products in one study in Nairobi, Kenya, were reported to have failed the requisite tests. Conclusions: There is an urgent need to strengthen pharmaceutical management systems such as post-marketing surveillance and the broader health systems in Africa to ensure populations in the continent have access to antimalarial drugs that are safe, of the highest quality standards and that retain their integrity throughout the distribution chain through adequate enforcement of existing legislation and enactment of new ones if necessary, and provision of the necessary resources for drug quality assurance. [source] | ||||||||||