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Zusammenfassung Es wird ein Index definiert, der den Grad, in dem ein Intelligenz- oder Leistungstest die Eigenschaften und Bedingungen eines ideal-typischen Niveau-Tests erfüllt, kennzeichnet. Der Index variiert in den Grenzen von 0 bis 1, wobei der Wert 0 einem idealtypischen Schnelligkeitstest (Speed-Test) und der Wert 1 einem idealtypischen Niveau-Test entspricht. Dieser Index kann aufgrund einer einmaligen Testdurchführung bestimmt werden; er ist abh?ngig von der Zeitbegrenzung des Testes und vom Leistungsniveau der untersuchten Stichprobe. Es wird vorgeschlagen, einen Test mitw> > 0,7 als Niveautest, einen solchen mitw<0,3 als Schnelligkeitstest zu bewerten. Die Berechnung vonw wird an Hand bekannter Tests demonstriert und einige Anwendungsbeschr?nkungen er?rtert.
Summary An index (w) for determining a test as to its degree of being a speed or a power test is proposed varying like a coefficient of correlation from zero to one. This index may be derived from a single testing a posteriori. It is dependent on the given time limit and on the achievement level of the sample tested. From empirical evidence it is suggested to accept a test with an indexw>0,7 as a power test and a test withw<0,3 as a speed test. Numerical examples for calculatingw are given and some restrictions for its application are discussed.


Herrn Prof. H. Münzner (Berlin) danken die Verfasser für die Durchsicht des Manuskriptes und für seine wertvollen Anregungen.  相似文献   
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Dr. H. Vogt 《Metrika》1978,25(1):49-58
Summary If 1, 2,..., n and 1, 2,..., –1 are two ordered samples from a population with continuous distribution functionF(x), then the points ( r ,r/n),r=1, 2,..., n–1 provide a better approximation ofF(x) than the points ( r ,r/n),r=1, 2,..., n, in the following sense:A maximal upper deviation and a maximal lower deviation of more theny have — contrary to the points ( r ,r/n) — equal probability for anyy0, if we deal with the points ( r ,r/n). This probability is at least for ally in the interval , 1 less than the probability for a maximal upper deviation of more thany in the case of the points ( r ,r/n). This is shown by a comparison of the Smirnow-Birnbaum-Tingey — formula with an analogous formula for the maximal one-sided deviations of the points( r ,r/n).  相似文献   
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Summary Pseudo Bayesian estimators for the variance components based on Jeffrey’s Rule are derived for the mixed balanced incomplete block design and are compared with the usual analysis of variance estimators in terms of mean squared error (MSE) efficiency. Numerical results show that Pseudo-Bayesian estimators are more efficient in numerical results.  相似文献   
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Dr. R. Arnab 《Metrika》1988,35(1):233-239
Summary Postulating an intra-class correlation structure for a finite population vector of variate — values optimal stratified and unstratified strategies for estimating the total are identified and relative efficiencies noted. Higher efficiency of stratified over unstratified sampling is demonstrated for usual estimators in ppswr case, in particular. In the uncorrelated case appropriately chosen two-stage strategies are observed to fare at par with optimal stratified ones.  相似文献   
66.
Poly-t densities are defined by the property that their kernel is a product, or ratio of products, of Student-t kernels. These multivariate densities arise as Bayesian posterior densities for regression coefficients, under a surprising variety of specifications for the prior density and the data generating process. Although no analytical expression exists for the integrating constant and moments of these densities, these parameters are obtained through numerical integration in a number of dimensions given by the number of Student-t kernels in the numerator, minus one. The paper reviews how poly-t densities arise in regression analysis, and summarizes the results obtained for a number of models.  相似文献   
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In the second half of 2009, the entire media agenda in Germany was dominated by the swine flu, next to the German Federal Parliament elections. Criticism was voiced in the media against the pharmaceutical industry for lobbying the nationwide swine flu vaccination, which was widely considered nothing but a product of the industry’s lobbying power. In order to avoid the usual interviews with lobbyists, we attempted to apply a new methodological framework approach in analysing lobbying processes and key stakeholders in the public sphere—and outside. Crucial to the diversified approach, which involves quantitative content analysis of media coverage and press releases, are interviews with journalists, lobbyists’ network analysis and internet research on biographies. Although a conspiracy could not be conclusively proven, the results do indicate associations that validate the criticism of the industry’s lobbying activities.  相似文献   
70.
In this paper we discuss how repetition of a single statement affects its perceived credibility. Using an experimental design, our results support previous psychological studies on the “truth-effect”, which have shown that repeated messages are considered more credible than non-repeated messages. In addition, our study sheds light on the unanswered question why the truth-effect vanishes or reverses if statements are repeated too often. Analysis strongly points to a parallel, indirect negative effect, caused by participants showing reactance as a consequence of repetition.  相似文献   
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