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251.
Lynette K. Chandler Susan A. Fowler Roger C. Lubeck 《Journal of applied behavior analysis》1992,25(2):249-263
We examined the effects of four combinations of setting events on the social interactions of 7 preschool children with social delays. In Study 1, the status of the teacher, activity materials, and peer varied across conditions. In Study 2, the status of the teacher and materials varied across conditions. Within the combinations of setting events, we also examined teacher behavior. Teacher presence and absence was varied in both studies. The type and rate of teacher prompting were varied in Study 2. The four combinations of setting events produced different rates of social behavior by the children with social delays. The optimal combination of setting events for promoting peer interaction and reducing teacher—child interaction included teacher absence from the activity, a limited number and form of materials, and children paired with a socially skilled partner. 相似文献
252.
Samuel L. Odom Lynette K. Chandler Michaelene Ostrosky Scott R. McConnell Susan Reaney 《Journal of applied behavior analysis》1992,25(2):307-317
This study examined a system for fading teacher prompts to children who served as peers in peer-initiation interventions for young children with disabilities. A teacher taught peers to direct social initiations to children with disabilities, provided verbal prompts for those initiations, and introduced a system that provided peers with visual feedback about the social interactions of the children with disabilities. She then systematically withdrew the verbal prompts to peers, and subsequently faded the visual feedback system. Peer initiations increased when the intervention began and resulted in increases in social interaction for the children with disabilities. As the teacher systematically faded the prompts and visual feedback to the peers, social interaction continued at the levels found during intervention and was maintained during a short maintenance period. 相似文献
253.
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
254.
Anthony J. Cuvo Paula K. Davis Mark F. O'Reilly Brenda M. Mooney Ruth Crowley 《Journal of applied behavior analysis》1992,25(2):477-489
We assessed whether written task analyses would serve as textual prompts for performing functional tasks by persons with mild disabilities. Several variables that could influence the effectiveness of textual prompts to promote stimulus control were examined across four groups. A consistent finding was that written specific task analyses combined with end-of-trial performance feedback were effective for promoting the acquisition and generalization of several tasks. Performance transferred immediately to natural discriminative stimuli when the written task analyses and feedback were withdrawn for most tasks and participants. For 2 participants, transfer of stimulus control was accomplished by prompt fading, using individualized written task analyses either with or without performance feedback (Group 1). When feedback was not provided, the effectiveness of written specific task analyses was inconsistent across groups. In contrast to the controlling effects of written specific task analyses, written generic task analyses, which specified only major task outcomes, when combined with performance feedback (Group 1) did not control responding. Overall, this research demonstrated the effectiveness of written specific task analyses and performance feedback to promote stimulus control for persons with mild disabilities. 相似文献
255.
256.
B H Repp 《Perception & psychophysics》1992,51(1):14-32
This study investigated whether the apparent completeness of the acoustic speech signal during phonemic restoration derives from a process of auditory induction (Warren, 1984) or segregation, or whether it is an auditory illusion that accompanies the completion of an abstract phonological representation. Specifically, five experiments tested the prediction of the auditory induction (segregation) hypothesis that active perceptual restoration of an [s] noise that has been replaced with an extraneous noise would use up a portion of that noise's high-frequency energy and consequently change the perceived pitch (timbre, brightness) of the extraneous noise. Listeners were required to compare the pitch of a target noise, which replaced a fricative noise in a sentence, with that of a probe noise preceding or following the speech. In the first two experiments, a significant tendency was found in favor of the auditory induction hypothesis, although the effect was small and may have been caused by variations in acoustic context. In the following three experiments, a larger variety of stimuli were used and context was controlled more carefully; this yielded negative results. Phoneme identification responses collected in the same experiments, as well as informal observations about the quality of the restored phoneme, suggested that restoration of a fricative phone distinct from the extraneous noise did not occur; rather, the spectrum of the extraneous noise itself influenced phoneme identification. These results suggest that the apparent auditory restoration which accompanies phonemic restoration is illusory, and that the schema-guided process of phoneme restoration does not interact with auditory processing. 相似文献
257.
Fixed-ratio pausing: Joint effects of past reinforcer magnitude and stimuli correlated with upcoming magnitude 总被引:8,自引:8,他引:0 下载免费PDF全文
Pigeons responded on fixed-ratio schedules ending in small or large reinforcers (grain presentations of different duration) interspersed within each session. In mixed-schedule conditions, the response key was lit with a single color throughout the session, and pausing was directly related to the past reinforcer (longer pauses after large reinforcers than after small ones). In multiple-schedule conditions, different colors accompanied the ratios ending in small and large reinforcers, and pausing was affected by the upcoming reinforcer as well as the past one. Pauses were shorter before large reinforcers than before small ones, but they continued to be longer after large reinforcers than after small ones. The influence of the past reinforcer was modulated by the magnitude of the upcoming reinforcer; in the presence of the stimulus before the small reinforcer, the effect of the past reinforcer was enhanced relative to its effect in the stimulus before the large reinforcer. These results show that pausing between ratios is jointly determined by two competing factors: past conditions of reinforcement and stimuli correlated with upcoming conditions. 相似文献
258.
Discriminability between alternatives in a switching-key concurrent schedule 总被引:1,自引:1,他引:0 下载免费PDF全文
Six pigeons were trained to discriminate between two intensities of white light in a symbolic matching-to-sample procedure. These stimuli were then used to signal which schedule was available on the main key in a switching-key concurrent schedule. The concurrent schedules led to a symbolic matching-to-sample phase in which the subject identified the concurrent schedule to which it last responded before a reinforcer could be obtained. The concurrent schedules were varied across conditions. Discriminability, measured during the symbolic matching-to-sample performance, was high throughout and did not differ across the two procedures. Performance in the concurrent schedules was like that typically obtained using these schedules. Delays were then arranged between completion of the concurrent schedules and presentations of the symbolic matching-to-sample phase. A series of conditions with an intervening delay of 10 s showed that both concurrent-schedule performance and symbolic matching-to-sample performance were affected by the delay in a similar way; that is, choice responding was closer to indifference. 相似文献
259.
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
260.
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