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During the last several decades, the ethnic and racial composition of the American elite has changed to include some ethnic minorities and women. This study examines changes in the composition of one segment of the American elite: those who have obtained eminence in their occupations. Lieberson and Carter's study of the ethnic composition of eminent Americans, using Who's Who in America, is replicated with data from the 1990s (Lieberson and Carter, 1979, American Sociological Review 44:347–366). In addition, comparisons between blacks listed in Who's Who in America and blacks listed only in Who's Who among Black Americans are made. During the 20 years since Lieberson and Carter's study, Jews have made remarkable gains in eminent membership, while the rate of black representation has increased only moderately. Women are a small percentage of the eminent regardless of ethnicity, although black women are better represented than their counterparts in white ethnic groups.  相似文献   
3.
Summary.  We detail a general method for measuring agreement between two statistics. An application is two ratios of directly standardized rates which differ only by the choice of the standard. If the statistics have a high value for the coefficient of agreement then the expected squared difference between the statistics is small relative to the variance of the average of the two statistics, and inferences vary little by changing statistics. The estimation of a coefficient of agreement between two statistics is not straightforward because there is only one pair of observed values, each statistic calculated from the data. We introduce estimators of the coefficient of agreement for two statistics and discuss their use, especially as applied to functions of standardized rates.  相似文献   
4.
If a population contains many zero values and the sample size is not very large, the traditional normal approximation‐based confidence intervals for the population mean may have poor coverage probabilities. This problem is substantially reduced by constructing parametric likelihood ratio intervals when an appropriate mixture model can be found. In the context of survey sampling, however, there is a general preference for making minimal assumptions about the population under study. The authors have therefore investigated the coverage properties of nonparametric empirical likelihood confidence intervals for the population mean. They show that under a variety of hypothetical populations, these intervals often outperformed parametric likelihood intervals by having more balanced coverage rates and larger lower bounds. The authors illustrate their methodology using data from the Canadian Labour Force Survey for the year 2000.  相似文献   
5.
Abstract. This document presents a survey of the statistical and combinatorial aspects of four areas of comparative genomics: gene order based measures of evolutionary distances between species, construction of phylogenetic trees, detection of horizontal transfer of genes, and detection of ancient whole genome duplications.  相似文献   
6.
Through the use of two central Bakhtinian concepts, authoritative and internally persuasive discourse (word), this paper examines the tension between the ideology of linguistic hegemony as a source of power in the Greek public sphere and the condition of language shift faced by the Albanian‐speaking communities of modern Greece. I argue here that a cautious application of these two notions, which are relevant to linguistic ideology, can reveal crucial aspects of two processes: that of subordination to and that of questioning of the dominant linguistic ideology by local Albanian‐speaking communities. Thus, in language shift contexts, it is possible that no simple relations obtain that place social agents in unquestionable and easily predictable positions. Such an approach proves useful for the sociolinguistic study of threatened language communities.  相似文献   
7.
Maximum likelihood estimation and goodness-of-fit techniques are used within a competing risks framework to obtain maximum likelihood estimates of hazard, density, and survivor functions for randomly right-censored variables. Goodness-of- fit techniques are used to fit distributions to the crude lifetimes, which are used to obtain an estimate of the hazard function, which, in turn, is used to construct the survivor and density functions of the net lifetime of the variable of interest. If only one of the crude lifetimes can be adequately characterized by a parametric model, then semi-parametric estimates may be obtained using a maximum likelihood estimate of one crude lifetime and the empirical distribution function of the other. Simulation studies show that the survivor function estimates from crude lifetimes compare favourably with those given by the product-limit estimator when crude lifetimes are chosen correctly. Other advantages are discussed.  相似文献   
8.
Abstract.  We correct two proofs concerning Markov properties for graphs representing marginal independence relations.  相似文献   
9.
This paper presents a new Laplacian approximation to the posterior density of η = g(θ). It has a simpler analytical form than that described by Leonard et al. (1989). The approximation derived by Leonard et al. requires a conditional information matrix Rη to be positive definite for every fixed η. However, in many cases, not all Rη are positive definite. In such cases, the computations of their approximations fail, since the approximation cannot be normalized. However, the new approximation may be modified so that the corresponding conditional information matrix can be made positive definite for every fixed η. In addition, a Bayesian procedure for contingency-table model checking is provided. An example of cross-classification between the educational level of a wife and fertility-planning status of couples is used for explanation. Various Laplacian approximations are computed and compared in this example and in an example of public school expenditures in the context of Bayesian analysis of the multiparameter Fisher-Behrens problem.  相似文献   
10.
Technology continues to challenge the public relations practitioner to find ways to inform key constituents. The new technology has given rise to the “new journalism” that includes a declining traditional media and exploding internet media filled with websites and bloggers. The question posed by this research asks: Does the public relations practitioner inherit the same protection offered by “qualified privilege” that is most often associated with the traditional “press” or “reporter?” The research lays a foundation with an examination of defamation and the defense of qualified privilege. The research concludes that if information gathered by the public relations practitioner meets the “intent” and “content” tests, the information qualifies as news. Passing the “news” test, the defense of “qualified privilege” also attaches to the public relations practitioner.  相似文献   
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