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141.
142.
This paper provides a review of recent Supreme Court decisions stemming from the implementation of voluntary AAPs that include preferential treatment as a remedy; the evidence and proof required to establish and defend against reverse discrimination claims is identified. Overall, the courts sanctioned the use of preferential treatment if it occured as part of a well-conceived AAP. However, differences were found in the manner in which the courts adjudicated Title VII and constitutional claims of preferential treatment. The discussion examines research on the potential effects of voluntary AAPs on important organizational and societal outcome variables. We conclude that the impact of AAPs is likely to be far-reaching, exerting an effect possibly well beyond the limits considered in court decisions.  相似文献   
143.
The aptitude tests used to help make personnel decisions about military recruits were validated against hands-on tests of job performance in two Marine Corps occupational specialties, radio repairers and automotive mechanics. The tests were administered by Marine Corps noncommissioned officers. Marine Corps units provided the test administrators, testing facilities, and examinees. Data collected under such conditions are filled with errors that reduce the accuracy of validity coefficients. This paper shows how validity coefficients can be made more accurate by exercising quality control during the statistical analysis.  相似文献   
144.
Test theory without an answer key   总被引:2,自引:0,他引:2  
A general model is presented for homogeneous, dichotomous items when the answer key is not known a priori. The model is structurally related to the two-class latent structure model with the roles of respondents and items interchanged. For very small sets of respondents, iterative maximum likelihood estimates of the parameters can be obtained by existing methods. For other situations, new estimation methods are developed and assessed with Monte Carlo data. The answer key can be accurately reconstructed with relatively small sets of respondents. The model is useful when a researcher wants to study objectively the knowledge possessed by members of a culturally coherent group that the researcher is not a member of.This research was supported by NSF Grant No. SES-8320173 to the authors. We gratefully acknowledge comments and suggestions from John Boyd, Tarow Indow, and Kathy Maher as well as the editor and several anonymous referees.  相似文献   
145.
This paper gives a method for determining a sample size that will achieve a prespecified bound on confidence interval width for the interrater agreement measure,. The same results can be used when a prespecified power is desired for testing hypotheses about the value of kappa. An example from the literature is used to illustrate the methods proposed here.  相似文献   
146.
We obtain in this paper a representation of the formulae of extensions ofL by generalized quantifiers through functors between categories of first-order structures and partial isomorphisms. The main tool in the proofs is the back-and-forth technique. As a corollary we obtain the Caicedo's version of Fraïssés theorem characterizing elementary equivalence for such languages. We also discuss informally some geometrical interpretations of our results.  相似文献   
147.
148.
Summary The distinction is drawn between the metatheoretical commitments of Gestalt theory and their instantiations in explicit theory. It is argued that the metatheoretical commitments of Gestalt theory reflect important insights which might have served as the foundation of a theory of perception that avoids a number of the major difficulties associated with constructivism and the theory of direct perception. For this reason rehabilitation of the reputation of Gestalt theory is urged. In the concluding section certain similarities between the foundational premises of Gestalt theory and parallel distributed processing approaches are noted.The contents of this paper were presented initially at a symposium on perceptual theory in honor of Irvin Rock which convened in Washington, DC, on the occasion of the 1986 meetings of the American Psychological Association  相似文献   
149.
Stress in time     
The goals of this research were to determine whether speakers adjust the stress patterns of words within sentences to create an alternation between strong and weak beats and to explore whether this rhythmic alternation contributes to the characteristics stress differences between two major lexical categories of English. Two experiments suggested that speakers do alter lexical stress in accordance with rhythmic biases. When speakers produced disyllabic pseudowords in sentence contexts, they were more likely to place stress on the first syllable when the pseudoword was preceded by a weak stress and followed by a strong one than when the strong stress preceded and the weak followed. This occurred both when the pseudowords served as nouns and when they served as verbs. Text analyses further revealed that weakly stressed elements precede nouns more often than verbs, whereas such elements follow verbs more often than nouns. Thus, disyllabic nouns are more likely than disyllabic verbs to occupy contexts biased toward trochaic rhythm, a finding consistent with leftward dominant stress in disyllabic English nouns. The history of stress changes in English nouns and verbs also conforms with the view that rhythmic context may have contributed to the evolution of stress differences. Together, the findings suggest that the citation stress patterns of words may to some degree reflect adaptations of lexical knowledge to conditions of language performance.  相似文献   
150.
Perception of translational heading from optical flow   总被引:3,自引:0,他引:3  
Radial patterns of optical flow produced by observer translation could be used to perceive the direction of self-movement during locomotion, and a number of formal analyses of such patterns have recently appeared. However, there is comparatively little empirical research on the perception of heading from optical flow, and what data there are indicate surprisingly poor performance, with heading errors on the order of 5 degrees-10 degrees. We examined heading judgments during translation parallel, perpendicular, and at oblique angles to a random-dot plane, varying observer speed and dot density. Using a discrimination task, we found that heading accuracy improved by an order of magnitude, with 75%-correct thresholds of 0.66 degrees in the highest speed and density condition and 1.2 degrees generally. Performance remained high with displays of 63-10 dots, but it dropped significantly with only 2 dots; there was no consistent speed effect and no effect of angle of approach to the surface. The results are inconsistent with theories based on the local focus of outflow, local motion parallax, multiple fixations, differential motion parallax, and the local maximum of divergence. But they are consistent with Gibson's (1950) original global radial outflow hypothesis for perception of heading during translation.  相似文献   
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