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981.
982.
983.
We evaluated methods for comparing the effects of dextroamphetamine (Dexedrine), thioridazine (Mellaril), and contingency management in the control of severe behavior problems. A reversal design was used in which medications were systematically titrated and assessed in unstructured as well as structured settings with three clients. Subsequently, behavioral procedures including timeout, differential reinforcement of other behavior, and visual screening, were used in a multiple-baseline design across settings. The assessment and design methods were useful in comparing the interventions. Dextroamphetamine decreased inappropriate behaviors and improved academic behaviors in one client, but no reliable effects were observed in the other two clients. Thioridazine was variable across clients, settings, behaviors, and dosages. Contingency management produced consistent decreases in inappropriate behaviors and small improvements in academic performance.  相似文献   
984.
Subjects in Santa Barbara, California, and Groningen, The Netherlands, participated in a seven-person social dilemma game, presented in terms of a conservation of resources problem. Prior to their decision making in the social dilemma game, subject's social motive (altruistic, cooperative, individualistic, competitive) was assessed by means of two different classification procedures. On the basis of previous research findings American subjects were expected to display relatively more competitive social motives, and Dutch subjects relatively more cooperative ones. However, no indications of crosscultural differences were found neither with regard to the distribution of social motives nor with regard to the amount of resources taken for self in the social dilemma game. In both locations, competitive subjects took most resources for self, individualistic subjects took next most, cooperative subjects took less than individualists, and altruistic subjects took the least. In addition to predictive validity, indices of the convergent validity of two social motive assessment procedures were described.  相似文献   
985.
An experiment is reported in which the effects of taxonomic organization on 7-year-old and 11-year-old children's free and cued recall of two- and four-category lists were examined. The data were analyzed using a stages-of-learning model that simultaneously delivers estimates of the impact of these manipulations on storage and retrieval components of recall. The results indicated that for the Grade 2 children providing a category label at the time of recall primarily enhanced storage whereas increasing the number of categories primarily enhanced retrieval. For Grade 6 children, on the other hand, the use of category labels to cue recall primarily enhanced retrieval, whereas increasing the number of categories affected both storage and retrieval in free recall, but only retrieval in cued recall. In addition, while older children were superior to younger children at both storing and retrieving information, age differences at retrieval were generally larger than those at storage.  相似文献   
986.
The use of spelling-sound information in both reading and spelling was evaluated by having children read and spell nonwords and five types of words that differed in terms of their regularity for reading and spelling. The subjects were grade 3 children who had been psychometrically defined as good readers and good spellers (“good”), good readers and poor spellers (“mixed”), or poor readers and poor spellers (“poor”). Results indicated that all children attempted to use spelling-sound correspondences in both reading and spelling, although children in both the mixed and the poor groups had weaker knowledge of these correspondences and were less systematic in their use of them. Furthermore, even though the children in the mixed group had been matched with children in the good group on reading comprehension, the number and type of errors made by the mixed subjects on both the reading and spelling tasks were more similar to those of the poor subjects than to those of the good subjects.  相似文献   
987.
988.
A certain family of three-state Markov processes has been widely used in experiments on children's memory. Although the statistical machinery for these models is well developed in most respects, two shortcomings have been noted in recent literature reviews. First, the parameters of the models are not identifiable. Second, goodness-of-fit tests are laborious to execute and their sampling distributions are unknown. New procedures for dealing with these difficulties are reported.  相似文献   
989.
Data relating novelty preference to age for normal children are inconsistent, although a current theory predicts a developmental shift from novelty to familiarity preference in selective learning (D. Zeaman, 1976, in T. J. Tighe & R. N. Leaton (Eds.), Habituation: Perspectives from child development, animal behavior, and neurophysiology (pp. 297–320), Hillsdale, NJ: Erlbaum). Support for this theory, however, has been derived primarily from studies of retardate learning. Normal children's novelty preference was examined within a modified Moss-Harlow (E. Moss & H. F. Harlow, 1947, Journal of Comparative and Physiological Psychology, 40, 333–342) design to compare Zeaman's model with that of S. L. Witryol and W. Wanich (1983, The Journal of Genetic Psychology, 143, 3–8). Each of 16 problems, consisting of three single-stimulus demonstration trials and one two-choice test, was administered to 180 children (mean CA 4, 5.5, and 7 years) in three reward conditions. Novelty was manipulated by varying stimulus familiarization in the demonstration trials. Experiment 1 showed strong preferences for novel over familiar (demonstrated) stimuli at each age. Experiment 2 revealed novelty preference across age levels, two levels of reward contrast, and two levels of task difficulty. It was reasoned that Moss-Harlow tasks designed for normal children typically present a much higher level of difficulty than that intended by researchers. Furthermore, developmental decreases in novelty preference by retardates may derive from (a) transfer of training from prior experiments and (b) specific, repetitive instructions which may have directed attention away from stimulus novelty.  相似文献   
990.
Four experiments examined the control of observing responses by information feedback during visual discrimination learning. Second-grade children participated in Experiment 1; kindergarten, second-, and fifth-grade children were subjects in Experiments 2 and 3, and grade 5 and adult subjects were tested in Experiment 4. In order to view the stimuli, subjects in Experiments 1, 2, and 3 activated lights in viewing boxes; in Experiment 4, stimulus fixations were measured using a corneal reflection technique. Fifth graders and adults observed the discriminative stimuli for longer times on trials following negative feedback than on trials following positive feedback; in contrast, kindergartener's observing was not affected by type of feedback. Second graders showed smaller and less reliable reactions to type of feedback than did older subjects. These results support the view that visual observing is controlled by cognitive processes associated with hypothesis testing.  相似文献   
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