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921.
The fibrin(ogen) degradation product concentration is another differential-diagnosis parameter for distinguishing between artificially blood-stained and essentially blood-stained CSF. Determination of the fibrin(ogen) degradation product concentration has been found to be a reliable method of recognizing natively and artificially blood-stained CSF as being different. 相似文献
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A multiple-answer multiple-choice test item has a certain number of alternatives,any number of which might be keyed. The examinee is also allowed to mark any number of alternatives. This increased flexibility over the one keyed alternative case is useful in practice but raises questions about appropriate scoring rules. In this article a certain class of item scoring rules called thebinary class is considered. The concepts ofstandard scoring rules and equivalence among these scoring rules are introduced in the misinformation model for which the traditional knowledge model is a special case. The examinee's strategy with respect to a scoring rule is examined. The critical role of a quantity called the scoring ratio is emphasized. In the case of examinee uncertainty about the number of correct alternatives on an item, a Bayes and a minimax strategy for the examinee are developed. Also an appropriate response for the examiner to the minimax strategy is outlined.Research partially supported under Grants N00014-67-A-0314-0022 from the Office of Naval Research and GS-32514 and MPS 75-07539 from the National Science Foundation. 相似文献
924.
Otto P. van Driel 《Psychometrika》1978,43(2):225-243
In the applications of maximum likelihood factor analysis the occurrence of boundary minima instead of proper minima is no exception at all. In the past the causes of such improper solutions could not be detected. This was impossible because the matrices containing the parameters of the factor analysis model were kept positive definite. By dropping these constraints, it becomes possible to distinguish between the different causes of improper solutions. In this paper some of the most important causes are discussed and illustrated by means of artificial and empirical data.The author is indebted to H. J. Prins for stimulating and encouraging discussions. 相似文献
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Jean-Luc P. Patry 《Psychological research》1978,40(2):195-206
Summary A set of stimuli to be used in psychological experiments is presented. Drawn spontaneously by the Ss, these stimuli are outline forms which can be freely reproduced in an experimental situation. The complexity and meaning-fulness of 100 forms were investigated. Meaningfulness depended on two variables: the probability of a given form having a certain meaning for a S, and the homogeneity of the meanings a given number of Ss ascribe to this form. Three types of meaningfulness could be distinguished: forms with one meaning only, ambiguous forms and nonsense forms. Complexity, homogeneity and probability of having a meaning are listed for all 100 forms.This research was carried out as part of a doctoral dissertation at the Department of Behavior Science of the Swiss Federal Institute of Technology in Zurich. The author expresses gratitude firstly to his supervisors, Professor H. Fischer and Professor K. Bättig, for their encouragement and criticism throughout the research. Thanks are also due to Professor Klaczko and Dr. H.U. Baumann for their many valuable suggestions, to Laurel Gutmann, Professor A. Flammer and Professor M. Perrez for their many helpful comments on earlier drafts of the paper, and to W.G. Hoffmann and R. Casetti for their further assistance. 相似文献
930.
The combined research of Horner (1972) and Monahan, Kuhn, and Shaver (1974) has demonstrated the existence of a stereotype of the female medical student as sex-role deviant and disinterested in sex. The present study examined the validity of this stereotype. Male and female medical students' scores on two psychometric measures were compared with the male and female college norms. The stereotype was not supported. Female medical students demonstrated no greater sex-role deviance than did their male counterparts. Furthermore, only male medical students indicated significantly less heterosexual interest than their same-sex norm.The authors wish to thank Dr. David G. Fish, who was involved in the original data collection. Support for the analyses of these data was obtained from Grant Number 607-1034-21 and from a Career Scientist Award, Number 607-1001-22, to the Junior Author. 相似文献