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1.
Journal of Nonverbal Behavior - Age-related deficits are often observed in emotion categorization tasks that include negative emotional expressions like anger, fear, and sadness. Stimulus... 相似文献
2.
Random effects regression mixture models are a way to classify longitudinal data (or trajectories) having possibly varying lengths. The mixture structure of the traditional random effects regression mixture model arises through the distribution of the random regression coefficients, which is assumed to be a mixture of multivariate normals. An extension of this standard model is presented that accounts for various levels of heterogeneity among the trajectories, depending on their assumed error structure. A standard likelihood ratio test is presented for testing this error structure assumption. Full details of an expectation-conditional maximization algorithm for maximum likelihood estimation are also presented. This model is used to analyze data from an infant habituation experiment, where it is desirable to assess whether infants comprise different populations in terms of their habituation time. 相似文献
3.
As important members of research teams, statisticians bear an ethical responsibility to analyze, interpret, and report data honestly and objectively. One way of reinforcing ethical responsibilities is through required courses covering a variety of ethics-related topics at the graduate level. We assessed ethics requirements for graduate-level statistics training programs in the United States for the 2013–2014 academic year using the websites of 88 universities, examining 103 biostatistics programs, and 136 statistics degree programs. We categorized programs’ ethics training requirements as required or not required. Thirty-one (35.1%) universities required an ethics course for at least some degree students. Sixty-two (25.5%) degree programs required an ethics course for at least some students. The majority (77.4%) of required courses were worth 0 or 1 credit. Of the 177 programs without an ethics requirement, 19 (10.7%) listed an ethics elective. Although a single ethics course is insufficient for instilling an ethical approach to science, degree programs that model expectations through coursework point to the value of ethics in science. More training programs should prepare statisticians to consider the ethical dimensions of their work through required coursework. Supplementary materials for this article are available online. 相似文献
4.
Simulation results are reported on methods that allow both within group and between group heteroscedasticity when testing the hypothesis that independent groups have identical regression parameters. The methods are based on a combination of extant techniques, but their finite-sample properties have not been studied. Included are results on the impact of removing all leverage points or just bad leverage points. The method used to identify leverage points can be important and can improve control over the Type I error probability. Results are illustrated using data from the Well Elderly II study. 相似文献
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From the inception of the proportional representation movement it has been an issue whether larger parties are favored at
the expense of smaller parties in one apportionment of seats as compared to another apportionment. A number of methods have
been proposed and are used in countries with a proportional representation system. These apportionment methods exhibit a regularity
of order, as discussed in the present paper, that captures the preferential treatment of larger versus smaller parties. This
order, namely majorization, permits the comparison of seat allocations in two apportionments. For divisor methods, we show
that one method is majorized by another method if and only if their signpost ratios are increasing. This criterion is satisfied
for the divisor methods with power-mean rounding, and for the divisor methods with stationary rounding. Majorization places
the five traditional apportionment methods in the order as they are known to favor larger parties over smaller parties: Adams,
Dean, Hill, Webster, and Jefferson.
Received: 5 August 2000/Accepted: 24 October 2001 相似文献
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Schmidt Philip R. 《Sociological Practice: A Journal of Clinical and Applied Sociology》2002,4(3):195-208
The historical relationship between the electoral college and controversial U.S. presidential elections, specifically with respect to conflict, is examined. The elections of 1800, 1824, 1860, 1876, 1888, 1968, and 2000 are examined. Aside from the 2000 election, there has been essentially no conflict in American history due to the electoral college. The constitutional structure and thinking behind the form of the electoral college is given, with emphasis on the federal aspects of the structure. The current movement to abolish the electoral college in favor of direct popular vote is depicted, along with the arguments against making that change. The conclusion is that we as a nation are far better off to retain the status quo than to make the called-for change. 相似文献
10.
Uta Gerhardt 《The American Sociologist》2002,33(2):5-39
This article places an episode in the history of sociological theory into intellectual history in the twentieth century. The
perspective is chronological as well as contextual. The themes are two theoretical approaches, both embedded in both American
and German history, Parsonian Systems Theory and “Frankfurt School” Critical Theory. The chronology shown spanned mainly from
the 1940s to the 1960s. The context of the two theories is a period that is crucial in twentieth century history. The protagonists
of the two approaches were, in the 1940s, Americans and Germans exiled in the United States. In the 1950s, both approaches
were affected by McCarthyism in different ways. The 1960s, however, were the culmination. The dynamics of the two approaches
led into a schism which came into the open on the occasion of the 1964 German Sociology Conference in Heidelberg celebrating
Max Weber. The article shows the stages in the evolution of the schism, emulating three acts in a drama. The final split was
over whether Weber or Marx should be the classic whose oeuvre was to influence sociological thinking today. My aim is to exemplify
how these two authoritative approaches in sociological theory, far from escaping the vagaries and vicissitudes of their times,
were embedded in twentieth-century history. 相似文献