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101.
102.
This study tested the effect of using the word stress in the measurement of self-reported occupational stressors and strains. Employees from two organizations responded to a questionnaire that included specific occupational stressors, strains, and 16 items in which the word stress was used. Survey respondents tended to interpret the word stress to refer both to employees' strains or reactions to the work environment and to job stressors or elements of the environment itself. Implications of these findings for occupational stress research are discussed.  相似文献   
103.
Adult men (N = 44) participated for 2 days (alcohol vs. placebo treatment) in a double-blind, crossover experiment. Performance on the Digit Symbol Substitution Task (DSST) and a visuomotor (VM) task was measured 4 times each day. On the alcohol-treatment day, data were obtained once during ascending breath alcohol levels (BALs), once during maximal BALs (0.05 or 0.10), and twice during descending BALs. Data were collected at the same time points on the placebo-treatment day. Limited evidence for acute tolerance was obtained with the DSST, but error rates on the VM task were higher during maximal and descending BALs. Error rates remained near placebo values, and participants displayed slightly greater caution, while BALs were ascending. Strategy scores on the VM task exceeded placebo scores during maximal intoxication. Data interpretation is focused on individuals in higher level (e.g., professional) positions.  相似文献   
104.
105.
The multiple and long-term effects of functional communication training relative to a common reductive procedure (time-out from positive reinforcement) were evaluated. Twelve children participated in a functional analysis of their challenging behaviors (Study 1), which implicated adult attention as a maintaining variable. The children were then matched for chronological age, mental age, and language age and assigned to two groups. One group received functional communication training as an intervention for their challenging behavior, and the second group received time-out as a contrast. Both interventions were initially successful (Study 2), but durable results were achieved only with the group that received functional communication training across different stimulus conditions (Study 3). Students whose challenging behaviors were previously reduced with time-out resumed these behaviors in the presence of naive teachers unaware of the children's intervention history. The value of teaching communicative responses to promote maintenance is discussed as it relates to the concept of functional equivalence.  相似文献   
106.
Conclusions It may seem to their opponents that they are trying to have their cake and eat it too. Postmodernists admit that their own paradigm must be and will be placed into question by future thinkers. But if they can anticipate an eventual reaffirmation of their paradoxical stand in an ongoing oscillating debate, then cannot it be said that they have arrived at a truth that transcends their time and place in history? And, if so, is not their fallibilist stance in fact self-referentially inconsistent? The response of postmodernists is the claim that each reaffirmation of a fallibilist epistemology and ethics throughout history is in fact sui generis. And this is the case because each reaffirmation has its own unique context within which it is made. Modernists will of course argue that these contextual differences are nonessential and irrelevant. And the debate over the problem of the One and the Many is once again launched in a new context. Thus far from running away from the paradoxical position that what they assert is both true and false, postmodernists revel in such inconsistencies.But does not such an ethical stance resemble the Sisyphean nightmare of being condemned to roll a heavy stone up a cliff only to have it keep falling back to the bottom ad infinitum? If no decision is innocent of doing some harm in the world, why should we bother to play the moral game at all? Indeed, what possible help is a postmodernist ethics when it comes to making some of the complex and crucial decisions we face today if it refuses to say anything substantial beyond the recommendations that we be cautious and balanced?And the postmodernist can only reply that we are letting our neurotic need for solid foundations frighten us. For ethics is an art not a science. There are no absolute rules. If we do not like the way the game is set up, then we are simply revealing our ultimate hubris in the face of a mystery requiring deep humility.  相似文献   
107.
The scale illusion (Deutsch, 1975) shows the importance of frequency range in the perceptual organization of a sequence of notes. This paper includes three experiments on the scale illusion. Experiments 1 and 2 demonstrated that if the structure of the pattern of notes used in the original scale illusion study is altered slightly, by adding or subtracting a pair of notes from the ends of the sequence, there is a significant decrease in the rate of frequency-based responses, suggesting a weaker illusion. Experiment 3 investigated two features of the note patterns that may have led to this change. Specifically, it asked whether the decrease in the strength of the illusion is due to (1) the nature of the notes at the extremes of the frequency range and/or (2) the nature of the notes at the crossing point of the two scales. While both sources were found to affect the strength of the scale illusion, the former had a greater influence.  相似文献   
108.
Assessors evaluated assessees'performances in one of three performance conditions in an assessment center simulation: a consistent performance condition, a within-assessee performance variation condition, or a between-assessee performance variation condition. Contrast effects influenced ratings of assessees when there was variation in performance within assessees. For each assessee, the low target performance was rated lower when the assessee's prior performance had been dissimilar (high) than when the assessee's prior performance had been similar (low). Contrast effects also infiuenced assessors'ratings of the target assessee when there was variation in performance among assessees. The low performing target assessee was rated significantly lower when he was evaluated with two high performers than when he was evaluated with two low performers. In addition, ratings obtained when there was performance variation among assessees were more accurate than those obtained when there was no performance variation, suggesting that under some circumstances contrast effects may not lead to inferior judgments.  相似文献   
109.
The detectability of surface curvatures defined by optical motion was evaluated in three experiments. Observers accurately detected very small amounts of curvature in a direction perpendicular to the direction of rotation, but they were less sensitive to curvatures along the direction of rotation. Variations in either the number of points (between 91 and 9) or the number of views (from 15 to 2) had little or no effect on discrimination accuracy. The results of this study demonstrate impressive visual sensitivity to surface curvature. Several characteristics of this sensitivity to curvature are inconsistent with many computational models for deriving three-dimensional structure from motion.  相似文献   
110.
The research was intended to identify the dimensions underlying self-perceived information needs and concerns of an elderly population. The spontaneously mentioned needs and concerns expressed in 271 letters from a sample of the population were extracted and a multidimensional scaling procedure was used to represent the 58 most frequently mentioned items in configurations of varying dimensionality. To interpret the multidimensional spaces, another sample of 176 elderly subjects was asked to rate the 58 concerns on eight properties. These ratings were then regressed onto the multidimensional configurations. The results indicate that the most frequently mentioned information needs and concerns of elderly persons can be parsimoniously understood in terms of three underlying dimensions: (1) Improving the Quality of Life vs Securing the Necessities of Life, (2) Health-related vs Not Health-related, and (3) Individual vs Societal Responsibility.  相似文献   
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