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251.
A linear utility model is introduced for optimal selection when several subpopulations of applicants are to be distinguished. Using this model, procedures are described for obtaining optimal cutting scores in subpopulations in quota-free as well as quota-restricted selection situations. The cutting scores are optimal in the sense that they maximize the overall expected utility of the selection process. The procedures are demonstrated with empirical data.  相似文献   
252.
253.
Reports were obtained from middle-class and working-class unemployed British men about change or lack of change since job loss in 37 different behaviors. The behaviors were grouped into Domestic Work, Domestic Pastimes, Other Pastimes, Book Reading, Recreations, Entertainment Through Money, and Social Contacts. Contrary to findings from 1930s research, significant increases in social contact and book reading were reported since job loss. Other significant increases were reported within all categories except Entertainment Through Money, where a significant decline was recorded. A number of social class differences were found. For instance, middleclass unemploycd men were significantly more likely than their working-class counterparts to report increased book reading for study and more visits to the public library. Working-class respondents were significantly more likely to report increased looking around shops without buying and reduced visits to the pub. Several significant associations between reported behavior changes and aspects of psychological and general health were observed.  相似文献   
254.
In an earlier note, a new metric for bounded response scales (MBR) was introduced which resembles the city-block metric but is bounded above. It was suggested the MBR may be more appropriate than minkowski metrics for data obtained with bounded response scales. In this article, some formal properties of the MBR are investigated and it is shown that it is indeed a metric. Empirical predictions are then derived from the MBR and contrasted with those of a “monotonicity hypothesis,” which holds that dissimilarity judgements tend to be biased towards overestimation of larger distances, and with the predictions of the minkowski metrics, which imply additivity of collinear segments. Some empirical results are presented which contradict the monotonicity hypothesis and the minkowski metrics, and favor the MBR. Finally, the logic used to motivate the MBR is invoked to define a subadditive concatenation for bounded norms in the one-dimensional case, which may be useful in psychophysical work where the upper bounds are often real, rather than due to the response scale. This concatenation predicts understimation for doubling and overestimation for halving and middling tasks.  相似文献   
255.
Electrographic (EEG, EOG, EMG) indices have been used for some decades in the definition of the stages of sleep and more recently in the diagnosis of sleep-related disorders, e.g., insomnia, despite the lack of detailed information concerning the precise relationship between such electrographic indices and behavioral and subjective criteria of sleep. Evaluation of the relationship between EEG, behavioral, and self-report measures of sleep onset latency and sleep duration was conducted using 17 young normal sleepers. The behavioral measure was provided by an apparatus which records subjects' button-press responses to an auditory stimulus presented at various interstimulus intervals (2, 5, and random 1, 2, 5, 7, and 10 min). The behavioral and stage 2 EEG estimates of sleep onset latency (SOL) and sleep duration (SD) were almost identical. The stage 1 EEG provided the shortest estimate of SOL; the self-report measure, the longest. The SD measures were in reverse order. There were no significant differences among the three interstimulus interval conditions (2, 5, and random min). Average response rates to the 50-dB chime were 100% during wakefulness, 81% during EEG stage 1, and 8% during EEG stage 2. Almost all stage 2 responding occurred during the first 5 min of each stage 2 period. The validity of electrographic indices as sleep criteria and the implications of the findings for the formulation of an adequate definition of sleep and its clinical measurement are discussed.  相似文献   
256.
The Gestalt studies demonstrated the tendency to visually organize dots on the basis of similarity, proximity, and global properties such as closure, good continuation, and symmetry. The particular organization imposed on a collection of dots is thus determined by many factors, some local, some global. We discuss computational reasons for expecting the initial stages of grouping to be achieved by processes with purely local support. In the case of dot patterns, the expectation is that neighboring dots are grouped as a function of proximity and similarity of contrast, by processes that are independent of the overall organization and the various global factors. We describe experiments that suggest a purely local relationship between proximity and brightness similarity in perceptual grouping.  相似文献   
257.
Nondeterministic programs occurring in recently developed programming languages define nondeterminate partial functions. Formulas (Boolean expressions) of such nondeterministic languages are interpreted by a nonempty subset of {T (“true”), F (“false”), U (“undefined)}. As a semantic basis for the propositional part of a corresponding nondeterministic three-valued logic we study the notion of a truth-function over {T, F, U} which is computable by a nondeterministic evaluation procedure. The main result is that these truth-functions are precisely the functions satisfying four basic properties, called \( \subseteq \) -isotonic, \( \subseteq \) ?-isotonic, hereditarily guarded, and hereditarily guard-using, and that a function satisfies these properties iff it is explicitly definable (in a certain normal form) from “if..then..else..fi”, binary choice, and constants.  相似文献   
258.
Studied the effects of attitude extremity on perceived consensus and willingness to ascribe trait terms to others with either pro or anti nuclear attitudes. Results showed that attitude extremity affected consensus estimates. Trait attributions revealed a clear effect for valence, especially for the extreme attitude groups. Subjects with extreme attitudes also ascribed more traits to both pro and anti others than subjects with relatively moderate attitudes.  相似文献   
259.
This article discusses the attenuating mechanisms of group psychotherapy that support and enhance analytic work with borderline patients in combined group and individual psychotherapy. A group case study is presented which addresses the manifestations and management of transference and countertransference in a combined treatment approach. Combined treatment was observed to respond effectively to both the intrapsychic and interpersonal difficulties of borderline patients. A multidimensional model for treating these patients in a community mental health setting is proposed.  相似文献   
260.
It is a well documented finding that letter identification may be impaired by the presence of neighboring characters. There is much less agreement about the exact nature of such lateral interference. Evidence has been obtained for feature-specific interference, and even feature-specific facilitation. Santee and Egeth (1980) suggested that feature-specific interference will mainly be observed in data-limited situations where stimuli are presented for short durations and positional uncertainty is involved. They further suggested that interference would be revealed in accuracy rather than latency measures.In our first experiment, similar exposure conditions were used to those suggested by Santee and Egeth. In a second experiment, however, a longer exposure duration was used, and latency measurements were also collected. In a third experiment, positional uncertainty was removed by foveal presentation, and with this high quality stimulus presentation only latency measurements could be obtained.In all these experiments clear evidence for feature-specific interference was found, both in accuracy and latency data, and these results also held up under the detectability/criterion analysis proposed by Estes (1982). From these findings it can be concluded that feature-specific interference occurs under a wide range of conditions, including those representative of normal reading.  相似文献   
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