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31.
A running-wheel-movement-detection system is described for use with an IBM-compatible system and a serial mouse. It is an adaptation of a system developed for use on a Commodore 64. The IBM-compatible system provides obvious advantages in speed, memory, data storage, and programming ease over the earlier Commodore 64 system.  相似文献   
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33.
Conlon and Garland (1993) demonstrated that information about the degree of project completion, as compared with information about sunk costs, seemed to be the driving force behind continued investment in an R&D project. In the present paper, we replicate and extend this work. In studies with experienced bank managers, Chinese graduate students, and advanced-level MBA students, we find overwhelming support for the importance of project completion on investment intentions, with no indication of typical sunk cost effects. We argue that our results support a goal substitution explanation for many escalation phenomena where, as progress moves forward on a project, completion of the project itself takes increasing precedence over other goals (e. g., economic profit) that may have been more salient at the time the project was initiated.  相似文献   
34.
A theory is proposed to explain the linkages between individual task goals and performance. Two cognitive constructs are postulated to mediate between task goals and performance:performance expectancy and performance valence. It is asserted that an individual's task goal has a positive influence on performance expectancy and a negative influence on performance valence. Performance expectancy is proposed to have a positive influence on performance while performance valence is proposed to have a negative influence on performance. Task ability is hypothesized to influence performance both directly and indirectly through its influence on performance expectancy. A laboratory experiment was designed to test the causal model proposed by the theory. A path analysis on the data from this experiment provides strong support for the model, with performance expectancy, performance valence, and task ability predicting 63% of the variance in performance on the laboratory task.  相似文献   
35.
The possibility of using prerecorded words and 2-sec. delayed speech feedback as reinforcement in the reconditioning of intelligible verbal responses in a chronic, neologistic schizophrenic patient was investigated. A test situation was devised which involved daily presentation of 100 stimulus word-picture cards to elicit verbal responses. The results indicated that both singly presented prerecorded words and delayed speech feedback apparently strengthened correct and intelligible verbal responding.  相似文献   
36.
A method for simulating non-normal distributions   总被引:11,自引:0,他引:11  
A method of introducing a controlled degree of skew and kurtosis for Monte Carlo studies was derived. The form of such a transformation on normal deviates [X N(0, 1)] isY =a +bX +cX 2 +dX 3. Analytic and empirical validation of the method is demonstrated.This work was done while the author was at the University of Illinois at Champaign-Urbana.  相似文献   
37.
Vocational research has focused on the occupational choice process and the individual's adjustment to work. Very little research has examined the job search process in which the individual must engage in order to implement occupational choices. This study examines one dimension of the job search process: the relationship between job source and subsequent work experiences. The data reveal that when the respondents initially entered the labor market, those relying on formal job sources tended to work in higher-level occupations and in jobs more closely related to their training than their counterparts who used other job sources. In the longer run, the labor market advantages associated with the use of formal job sources dissipated for the engineering majors but tended to persist for the business alumni.  相似文献   
38.
Cognitive advantage in sport: the nature of perceptual structures   总被引:1,自引:0,他引:1  
To extend and clarify the nature of the perceptual processes used by sport experts to perceive schematic sport information, two experiments used schematic football diagrams that varied in structure (structured vs. unstructured) and complexity (complex vs. easy). The primary objective was to examine and characterize the nature of the perceptual structures (chunks) that are initially encoded, stored, and subsequently retrieved. In Experiment 1, compared with nonexperts, experts recalled larger perceptual structures following the initial stimulus presentation of structured stimuli only, replicating the recall findings of previous research in other skill domains. Experiment 2 used a long-term memory recognition task and a sorting task. Experts had superior recall and recognition of structured stimuli only, along with more discriminating sorting criteria of perceptual structures within long-term memory. This suggests that experts possess a highly refined semantic network or organized, structured schematic information. This research extends and clarifies the similarities between the perceptual processes of experts in sport (i.e., football) and experts in skill domains that require obvious cognitive involvement (i.e., chess). The results are discussed with reference to the perceptual and conceptual chunking hypotheses. It is proposed that sport experts' knowledge of a conceptual category enables them to retrieve elements using a "generate-and-test process."  相似文献   
39.
Older and young adults' letter detection and lexical decision performance were examined as word frequency varied to determine whether there were age differences in word recognition. Allen and Madden (1989) found that older adults' pattern of reaction time (RT) across word frequency categories was different from young adults' pattern for a letter detection task. In this study, for both letter detection and lexical decision tasks, older adults exhibited a monotonically decreasing RT function as word frequency increased. However, young adults exhibited a nonmonotonic RT function across word frequency for the letter detection task but a monotonically decreasing RT function as word frequency increased for the lexical decision task. An expanded parallel input serial analysis model of word processing was hypothesized.  相似文献   
40.
A within-subject comparison was made of the effects of methylphenidate (Ritalin) and response cost in reducing the off-task behavior of two boys, 7 and 8 years of age, who had been diagnosed as having an attentional deficit disorder with hyperactivity. Several dosages of Ritalin (5 to 20 mg/day) were evaluated with the results indicating varying effects of the drug for both children. Response cost (with free-time as the reinforcer) was superior to Ritalin in raising levels of on-task behavior and in improving academic performance.  相似文献   
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