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901.
Research over the past decade and a half exploring the psychological dimensions of the definition of sexual harassment has converged on a three-factor model: gender harassment, unwanted sexual attention, and sexual coercion. The current study used confirmatory factor analysis to determine whether the most widely used sexual harassment survey, the U.S. Merit Systems Protection Board (USMSPB; 1981) survey, measures this three-factor structure. Data from a sample of the USMSPB's 1988 survey of Federal employees (n= 1070) and from a midwestern university's survey of undergraduates (n= 572) and graduate students, faculty, and staff (n= 575) were analyzed. The three-factor model fit reasonably well in all samples, but two survey items, measuring sexual assault and sexual favors, were weakly related to their respective factors. This model, however, was only marginally stable across female and male subsamples, and gender harassment and unwanted sexual attention had low discriminant validity. Both practical and theoretical implications are discussed.  相似文献   
902.
Tustin (1994) recently observed that an individual's preference for one of two concurrently available reinforcers under low schedule requirements (concurrent fixed-ratio [FR] 1) switched to the other reinforcer when the schedule requirements were high (concurrent FR 10). We extended this line of research by examining preference for similar and dissimilar reinforcers (i.e., those affecting the same sensory modality and those affecting different sensory modalities). Two individuals with developmental disabilities were exposed to an arrangement in which pressing two different panels produced two different reinforcers according to progressively increasing, concurrent-ratio schedules. When two dissimilar stimuli were concurrently available (food and a leisure item), no clear preference for one item over the other was observed, regardless of the FR schedules in effect (FR 1, 2, 5, 10, and 20). By contrast, when two similar stimuli were concurrently available (two food items), a clear preference for one item emerged as the schedule requirements were increased from FR 1 to FR 5 or FR 10. These results are discussed in terms of implications for conducting preference assessments and for selecting reinforcers to be used under training conditions in which response requirements are relatively high or effortful.  相似文献   
903.
Mechanical restraints are commonly used to reduce the risks associated with severe self-injurious behavior (SIB), but may result in movement restriction and adverse side effects (e.g., bone demineralization). Restraint fading may provide a method for decreasing SIB while increasing movement and reducing these side effects. In the current investigation, rigid arm sleeves and restraint fading (gradually reducing the rigidity of the sleeves) were used with 3 clients who engaged in hand-to-head SIB. Restraints and fading reduced the hand-to-head SIB of all clients. However, for 1 client, the addition of a water mist procedure further reduced SIB to near-zero levels. For a 2nd client, another form of SIB developed that was not prevented by the rigid sleeves. For a 3rd client, a topography of SIB that was not physically prevented by the rigid sleeves was also reduced when restraints and fading were introduced.  相似文献   
904.
We conducted a functional assessment of problem behaviors of 2 students with developmental disabilities in their classroom environments. Results of the assessments showed that although there were more tantrums in demand than in no-demand conditions, the function of the behavior was to gain attention (positive reinforcement) rather than to avoid or escape demands (negative reinforcement); demand conditions apparently served a discriminative function for the availability of attention. Therefore, intervention was based on the positive reinforcement hypothesis, resulting in a substantial reduction of tantrums for both subjects.  相似文献   
905.
One of the most important skills in soccer is the ability to respond quickly and accurately to the changing demands of the competitive environment (i.e., position of ball, teammates, opponents). A multiple baseline design across 4 male collegiate soccer players was used to determine the effectiveness of an attentional training program on the execution of targeted soccer skills. The treatment included information and laboratory attentional shift exercises followed by practice of attentional shifting skills on the execution of different soccer exercises. Following treatment, the accuracy of execution of the experimental soccer drill improved.  相似文献   
906.
This study evaluated the effectiveness of high-probability requests and time-out as treatments for noncompliance that appeared to be maintained by contingent attention in 2 developmental normal children. The introduction of high-probability requests increased compliance for 1 child but not the other. Time-out was effective with both children, and improvements in compliance were maintained at an 8-week follow-up.  相似文献   
907.
Discrete aimed hand movements, made by subjects given temporal-accuracy and time-minimization task instructions, were compared. Movements in the temporal-accuracy task were made to a point target with a goal movement time of 400 ms. A circular target then was manufactured that incorporated the measured spatial errors from the temporal-accuracy task, and subjects attempted to contact the target with a minimum movement time and without missing the circular target (time-minimization task instructions). This procedure resulted in equal movement amplitude and approximately equal spatial accuracy for the two task instructions. Movements under the time-minimization instructions were completed rapidly (M = 307 ms) without target misses, and tended to be made up of two submovements. In contrast, movements under temporal-accuracy instructions were made more slowly (M = 397 ms), matching the goal movement time, and were typically characterized by a single submovement. These data support the hypothesis that movement times, at a fixed movement amplitude versus target width ratio, decrease as the number of submovements increases, and that movements produced under temporal-accuracy and time-minimization have different control characteristics. These control differences are related to the linear and logarithmic speed-accuracy relations observed for temporal-accuracy and time-minimization tasks, respectively.  相似文献   
908.
Summary feedback involves withholding feedback from subjects until the last trial in a block is completed, and then presenting feedback about each trial. A variation of this method, called average feedback (Young & Schmidt, 1992), presents subjects with only the mean of the trial block. We investigated whether these methods have similar effects on acquisition and retention of a simple motor skill. Five groups of subjects (n = 16 per group) performed 60 acquisition trials of an aiming task involving both spatial and temporal accuracy. We presented average and summary feedback based on either 5-trial blocks or 15-trial blocks and compared these schedules with every-trial feedback. During acquisition, all groups improved with practice, with a slight tendency for the every-trial condition to have less absolute error than the longer summary and average conditions. Analysis of delayed no-feedback retention tests, however, revealed a strong advantage for the 5-trial summary and average conditions compared with the every-trial condition. In addition, we found that for long blocks of acquisition trials without augmented feedback, the performance variability of those trials was associated with retention performance. Results are discussed in terms of how these different manipulations may make feedback less useful during acquisition, but foster the use of certain information processing activities that enhance overall learning.  相似文献   
909.
910.
The purpose of this study was to investigate the effectiveness of a single session of cognitive restructuring in a sample of phobic dental patients. Fifty-two patients were randomly assigned to one of three conditions: cognitive restructuring (modification of negative cognitions), provision of information (about oral health and dental treatment), and a waiting list control condition. Both interventions maximally lasted one hour. In comparison with the waiting list control condition and the information intervention condition, the cognitive intervention condition not only showed a large decrease in frequency and believability of negative cognitions, but also exhibited a clear decline in dental trait anxiety. Analysis at a follow-up of one year demonstrated a further, drastic reduction in dental anxiety in both intervention conditions, wherein the difference among these conditions was not maintained. It is concluded that it is possible to obtain substantial reductions of dental trait anxiety through a single session of cognitive restructuring. Nevertheless, repeated exposure to the dental situation seems necessary for a further reduction of anxiety.  相似文献   
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