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941.
The combined and separate effects of parent-presented models and praise on specific vocalizations of three children (15, 17, and 20 months old) were investigated. The frequency of a specific vocalization was higher when parents modeled and praised it than when they did not. In addition, modeling and praise, when used in combination, had a greater effect on the frequency of specific vocalizations than when used separately. Three additional parents were asked to attempt, by any means they wished, to increase the frequency of a specific vocalization by their children. These parents used modeling almost, exclusively, and the children did not exhibit the specific vocalizations as frequently as did the children whose parents were instructed both to model and praise specific vocalizations.  相似文献   
942.
Noninstitutionalized, educable retarded, spastic cerebral palsied children of two mental age (MA) levels were compared with normal MA controls on a task measuring selective attention and were not found deficient in selective attention. For both the cerebral palsied and the normals there was an increase in selective attention efficiency with an increase in MA. The results support the position that MA rather than chronological age or IQ is the important variable in determining selective attention performance. The results do not support the attention-deficit theory; they do support the argument that institutionalization has a negative affect on attention. The effects of brain damage and retardation on selective attention ability were discussed.Thanks are expressed to Eleanor Rennie, Head Teacher, Robert Massie, Supervisor of Special Education, and E. F. DeFord, Assistant Director, Department of Research for the Richmond Public Schools, Richmond, Virginia. Appreciation is also given to Scott Hamrick, Principal, Jackson Via Elementary School, Charlottesville, Virginia. Susan Autrey is also thanked for assistance in data collection.  相似文献   
943.
Estimates of the point of intersection of converging line segments depended upon the angle between lines and the orientation of the display. Main conclusion: The tilt of a line is perceptually altered to appear more nearly parallel to the more closely aligned axis, either horizontal or vertical, of an O’s visual field.  相似文献   
944.
This study contrasts the effects of specific practice vs nonspecific practice in scanning for sets of five-letter targets. Ss were required to search for new targets after extended practice with one specific target set. Simultaneous memory search was not supported, since searching for one item remained faster than for several items. Serial exhaustive memory search was not supported since the search data were nonlinear. There is evidence that the categorization of a target, even after large amounts of specific practice, is not heavily dependent upon its physical features. A strategy change was detected during practice which allowed more efficient search. It is concluded that a single memory search process can account for the data under both high and low levels of specific practice.  相似文献   
945.
946.
947.
Explanations of the Poggendorff effect were tested by varying the separation between outer parallels and by adding interior parallels. Error decreased with the addition of interior parallels, which can be explained by repulsion of parallels. A strong linear trend existed for judgmental error in millimeters plotted against separation between outer parallels. The nonzero intercept of a best-fit line and the slight nonlinearity of the data suggest a hypothesis of contour repulsion between parallels at moderate separations coupled with mistracking of the transversal across the region between parallels. Since the Poggendorff effect was independent of viewing distance, perceptual errors cannot be explained by purely peripheral mechanisms. A true intersection between transversal and parallel was the most critical feature of a display. Inverting a display increased the mean error.  相似文献   
948.
Noncontingent reinforcement (NCR) and response blocking are 2 common interventions for problem behavior maintained by automatic reinforcement. We implemented NCR and blocking with 1 boy and found this combined intervention to be effective at decreasing high rates of automatically reinforced pica. With another child, we compared the effects of blocking alone to the combined intervention. With the third child, we compared NCR alone and blocking alone to the combined intervention. Results showed that the combined intervention was effective at reducing automatically reinforced problem behavior while moderate to high levels of item engagement maintained. When evaluated individually, neither NCR nor blocking was sufficient to reduce problem behavior to clinically significant levels.  相似文献   
949.
This article focuses on recent disturbing trends opposed to Christian unity in Nigeria that have both remote and immediate causes. Although the Christian Association of Nigeria (CAN) was formed to promote unity among the various Christian denominations in the country, it has not been able to achieve its goal. After describing this present situation and the historical factors that caused it, this paper looks to the resources of the Second Vatican Council which CAN should adopt to ease the tension in the country and promote greater dialogue. The article looks at the Roman Catholic‐Lutheran Declaration that was signed in 1999, and officially resolved the disagreements that led to the split led by Martin Luther in 1517. Finally this paper looks at the style of Pope Francis as a living example of effective ecumenism and interfaith dialogue.  相似文献   
950.
Small-sample inference with clustered data has received increased attention recently in the methodological literature, with several simulation studies being presented on the small-sample behavior of many methods. However, nearly all previous studies focus on a single class of methods (e.g., only multilevel models, only corrections to sandwich estimators), and the differential performance of various methods that can be implemented to accommodate clustered data with very few clusters is largely unknown, potentially due to the rigid disciplinary preferences. Furthermore, a majority of these studies focus on scenarios with 15 or more clusters and feature unrealistically simple data-generation models with very few predictors. This article, motivated by an applied educational psychology cluster randomized trial, presents a simulation study that simultaneously addresses the extreme small sample and differential performance (estimation bias, Type I error rates, and relative power) of 12 methods to account for clustered data with a model that features a more realistic number of predictors. The motivating data are then modeled with each method, and results are compared. Results show that generalized estimating equations perform poorly; the choice of Bayesian prior distributions affects performance; and fixed effect models perform quite well. Limitations and implications for applications are also discussed.  相似文献   
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