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241.
This experiment examined the processing of information from multiple element visual displays, using techniques derived from the theory of signal detectability. The method allows one to specify how observers integrate information from individual elements of a display. The experiment tested numerical and graphical displays having different display sizes, durations, and arrangements of elements. Observer performance increased with the number, m, of display elements, but at less than the ideal √m rate. Observer performance was consistent with a model of information integration constrained by internal noise. Linear arrays of elements resulted in better performance than did square arrays. Graphically coded elements resulted in better performance than did numerical elements. Observer decision weighting of element information from graphical displays was approximately uniform across spatial position, but the weighting of information from numerical displays was concentrated on elements near the fixation point.  相似文献   
242.
A longitudinal organizational field study examined work satisfaction and employee growth coping as joint predictors of turnover. Three employee categories were examined: 1) No Turnover, 2) turnover within the same occupational field (Intraoccupational Turnover), and 3) turnover to a new occupational field (Interoccupational Turnover). Work satisfaction was moderate in the first two groups and low in the third group. As predicted, a specific strategy of employee coping, growth, was lowest in the first group, moderate in the second group, and highest in the third group. Through the use of linear discriminant analysis, 66.4% of the employees were correctly classified into No Turnover, Intraoccupational Turnover, and Interoccupational Turnover groups based only on information regarding work satisfaction and growth coping. The first squared canonical correlation was found to equal .30, far surpassing the modest work satisfaction/turnover correlations found in all previous studies.The authors wish to thank the two anonymous reviewers for their thoughtful comments.  相似文献   
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Internal consistency of two forms of the Geriatric Treatment Acceptability Survey (GTAS) and the Attitudes toward Behavior Analysis Scale (ABAS), a global measure of attitudes toward behavior modification, was evaluated. Alpha coefficients regarding treatment acceptability ratings for GTAS Form H were: (a) wandering 0.94; (b) hoarding 0.96; (c) disruptive behavior 0.92; (d) property destruction 0.95; and (e) aggression 0.94. Internal consistency for Form NH was: (a) wandering 0.96; (b) hoarding 0.97; (c) disruptive behavior 0.96; (d) property destruction 0.97; and (e) aggression 0.76. Internal consistency of the ABAS resulted in alpha coefficients of 0.90 (total score); 0.87 (ethics and humaneness); and 0.76 (use). These measures appear useful in assessing older adults, nursing home patients' and geriatric nursing staffs' global and specific attitudes regarding the use of behavioral treatments with older adults. Further research is needed to establish psychometric constructs assessed by the instruments and sensitivity to detecting change in attitudes based on educational or clinical interventions.  相似文献   
246.
Reliable monitoring of the movement of small aquatic animals presents some unique problems. In the case of the larval salamander, the animal may be less than an inch long and move in sporadic short bursts. A device is described that utilizes infrared emitters and wide-band sensors inter-faced to a computer for monitoring location and movement of animals between light and dark environments over extended periods of time. The system employs a multiplexed digital input, is inexpensive, and can be easily expanded to deal with a range of monitoring problems that may occur with a wide range of both aquatic and terrestrial species.  相似文献   
247.
The current paradigm in medicine generally distinguishes between genetic and environmental causes of disease. Although the word paradigm has become a commonplace, the theories of Thomas Kuhn have not received much attention in the journals of medicine. Kuhn's structuralist method differs radically from the daily activities of the scientific method itself. Using linguistic theory, this essay offers a structuralist reading of Thomas Kuhn's The Structure of Scientific Revolutions. Our purpose is to highlight the similarities between these structuralist models of science and language. In part, we focus on the logic that enables Kuhn to assert the priority of perception over interpretation in the history of science. To illustrate some of these issues, we refer to the distinction between environmental and genetic causes of disease. While the activity of scientific research results in the revision of concepts in science, the production of significant differences that shape our knowledge is in part a social and linguistic process.  相似文献   
248.
We present a class of stimuli that makes it possible to study the interaction of visual attributes in forming textural patterns. These stimuli are obtained in a simple manner from a class of motion stimuli that we described earlier (Papathomas & Gorea, 1988). The main advantages of the texture stimuli presented in this paper are: (1) each attribute can be arranged simultaneously with, but independently of, other attributes, (2) an arbitrary number of attributes can be used, (3) the interaction of attributes can be studied systematically, (4) direct comparison of two attributes is possible with stimuli in which the two are arranged to form competing patterns, and (5) because of the similarity to the motion stimuli, the relationship between texture and motion mechanisms can be investigated.  相似文献   
249.
Adult subjects were presented with two auditory stimuli per trial, and their task was to decide which of the two was longer in duration. An adaptive psychophysical procedure was used. In Experiments 1, 2, and 4, the base duration was 50 msec, whereas in Experiment 3, the base duration was 1 sec. In Experiments 1, 2, and 4, it was found that filled intervals (continuous tones) were discriminated more accurately than empty intervals (with onset and offset marked by clicks). It was concluded that this difference was perceptual rather than cognitive in nature, since performance on filled and empty intervals was not affected by increasing cognitive load in a dual-task procedure (Experiment 2) but was affected by backward masking (Experiment 4). In contrast, the results of Experiment 3 showed that duration discrimination of filled auditory intervals of longer duration was cognitively influenced, since performance was impaired by increasing cognitive load. Implications for notions of perceptual processing and timing mechanisms tanderlying differences in duration discrimination with filled and empty intervals are discussed.  相似文献   
250.
Entrapping conflicts are those in which individuals continue to invest their resources—even in seemingly losing propositions-in large part to justify previous unfilled expenditures. It has been demonstrated that individuals define their motivation for investing very differently at the various stages of an entrapping conflict. One implication of this motivational dynamic is that various factors may differentially affect degree of entrapment (i.e., amount invested), depending upon the point in time at which they are introduced. The present studies were designed to test this notion. All subjects were given an initial monetary stake and had the opportunity to win more by taking part in an entrapping investment situation. In Experiment 1, half the subjects were provided with a payoff chart that made salient the costs associated with investing (Highcost salience condition) whereas half were not (Low-cost salience condition). Moreover, for half of the subjects the payoff chart was introduced before they were asked to invest (Early condition) whereas for the other half it was introduced after they had invested a considerable portion of their resources (Late condition). Entrapment was lower in the High salience-Early than in the Low salience-Early condition. However, there was no difference between groups in the Late condition. In Experiment 2, the perceived presence of an audience interacted with personality variables related to face-saving to effect entrapment. When the audience was described as “experts in decision making,” subjects high in public self-consciousness (or social anxiety) became less entrapped than those low on these dimensions. When the audience consisted of individuals who “wished simply to observe the experimental procedure,” however, high public self-consciousness (or social anxiety) individuals were significantly more entrapped than lows. Moreover, these interaction effects occurred when the audience was introduced late, but not early, into the entrapment situation. Taken together, these (and other) findings suggest that economic factors are more influential determinants of behavior in the earlier stages of an entrapping conflict, whereas face-saving variables are more potent in the later phases. Alternative explanations are discussed.  相似文献   
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