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91.
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Performance transferred immediately to natural discriminative stimuli when the written task analyses and feedback were withdrawn for most tasks and participants.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   
92.
The multiple and long-term effects of functional communication training relative to a common reductive procedure (time-out from positive reinforcement) were evaluated. Twelve children participated in a functional analysis of their challenging behaviors (Study 1), which implicated adult attention as a maintaining variable. The children were then matched for chronological age, mental age, and language age and assigned to two groups. One group received functional communication training as an intervention for their challenging behavior, and the second group received time-out as a contrast. Both interventions were initially successful (Study 2), but durable results were achieved only with the group that received functional communication training across different stimulus conditions (Study 3). Students whose challenging behaviors were previously reduced with time-out resumed these behaviors in the presence of naive teachers unaware of the children's intervention history. The value of teaching communicative responses to promote maintenance is discussed as it relates to the concept of functional equivalence.  相似文献   
93.
John Pais 《Studia Logica》1992,51(2):279-316
The properties of belief revision operators are known to have an informal semantics which relates them to the axioms of conditional logic. The purpose of this paper is to make this connection precise via the model theory of conditional logic. A semantics for conditional logic is presented, which is expressed in terms of algebraic models constructed ultimately out of revision operators. In addition, it is shown that each algebraic model determines both a revision operator and a logic, that are related by virtue of the stable Ramsey test.The author is grateful for a correction and several other valuable suggestions of two anonymous referees. This work was supported by the McDonnell Douglas Independent Research and Development program.  相似文献   
94.
We introduce two new belief revision axioms: partial monotonicity and consequence correctness. We show that partial monotonicity is consistent with but independent of the full set of axioms for a Gärdenfors belief revision sytem. In contrast to the Gärdenfors inconsistency results for certain monotonicity principles, we use partial monotonicity to inform a consistent formalization of the Ramsey test within a belief revision system extended by a conditional operator. We take this to be a technical dissolution of the well-known Gärdenfors dilemma.In addition, we present the consequential correctness axiom as a new measure of minimal revision in terms of the deductive core of a proposition whose support we wish to excise. We survey several syntactic and semantic belief revision systems and evaluate them according to both the Gärdenfors axioms and our new axioms. Furthermore, our algebraic characterization of semantic revision systems provides a useful technical device for analysis and comparison, which we illustrate with several new proofs.Finally, we have a new inconsistency result, which is dual to the Gärdenfors inconsistency results. Any elementary belief revision system that is consequentially correct must violate the Gärdenfors axiom of strong boundedness (K*8), which we characterize as yet another monotonicity condition.This work was supported by the McDonnell Douglas Independent Research and Development program.  相似文献   
95.
Four experiments tested the hypothesis that successful retrieval of an item from memory affects retention only because the retrieval provides an additional presentation of the target item. Two methods of learning paired associates were compared. In the pure study trial (pure ST condition) method, both items of a pair were presented simultaneously for study. In the test trial/study trial (TTST condition) method, subjects attempted to retrieve the response term during a period in which only the stimulus term was present (and the response term of the pair was presented after a 5-sec delay). Final retention of target items was tested with cued-recall tests. In Experiment 1, there was a reliable advantage in final testing for nonsense-syllable/number pairs in the TTST condition over pairs in the pure ST condition. In Experiment 2, the same result was obtained with Eskimo/English word pairs. This benefit of the TTST condition was not apparently different for final retrieval after 5 min or after 24 h. Experiments 3 and 4 ruled out two artifactual explanations of the TTST advantage observed in the first two experiments. Because performing a memory retrieval (TTST condition) led to better performance than pure study (pure ST condition), the results reject the hypothesis that a successful retrieval is beneficial only to the extent that it provides another study experience.  相似文献   
96.
A series of experiments investigated whether people could integrate nonspatial information about an object with their knowledge of the object's location in space. In Experiments 1 and 3, subjects learned the locations of cities on a fictitious road map; in Experiments 2, 4, and 5, subjects were already familiar with the locations of buildings on a campus. The subjects then learned facts about the cities on the maps or the buildings on the campus. The question of interest was whether or not these nonspatial facts would be integrated in memory with the spatial knowledge. After learning the facts, subjects were given a location-judgment test in which they had to decide whether an object was in one region of the space or another. Knowledge integration was assessed by comparing levels of performance in two conditions: (a) when a city or a building name was primed by a fact about a neighboring city or building, and (b) when a city or a building name was primed by a fact about a distant city or building. Results showed that responses in Condition a were faster or more accurate, or both faster and more accurate, than responses in Condition b. These results indicate that the spatial and nonspatial information were encoded in a common memory representation.  相似文献   
97.
During the 1990-1991 Persian Gulf conflict an experiment was conducted with Australian university students (N = 200) to investigate whether the social stereotyping of Americans varied with social contextual manipulations related to the hostilities. The study, conducted in two phases at the start and end of the conflict, examined how the assignment of standard stereotypical traits to Americans was affected (a) by the large-scale social change constituted by the war and (b) by variation in the frame of reference provided by relevant comparison groups. The elicited stereotypes were sensitive to both of these contextual variables, demonstrating significant variation and fluidity. Overall, stereotypes of Americans were relatively negative. They were significantly more negative (a) at the end of the war than at the beginning in the restricted frame (when Australia and Britain were comparison groups) and (b) in the first phase of the conflict when the frame was extended to include Iraq as a comparison group. The findings were in line with expectations derived from self-categorization theory (Turner, 1985) that the social categorization of self and other into ingroup and outgroup is inherently variable, comparative and context-dependent. They question the long-held view of stereotypes as fixed, rigid and resistant to change.  相似文献   
98.
This paper examines the hypothesis that patterns of stereotypic accentuation reflect the degree to which judged stimuli share the same social category membership as the stereotyper, Following self-categorization theory, the degree of this shared identity is operationalized in terms of the meta-contrast ratio as a function of the positions of (a) stereotyper and (b) stereotyped target relative to (c) the stereotyper's frame of reference. Three experiments are reported which sought to manipulate shared category membership either by extension of subjects' frame of reference or by extremitization of target and subject with respect to that frame. As predicted, greater shared identity was associated with stronger assimilation of the target to subjects' own position and with change in stereotype content. Findings are discussed in relation to theories of personality, social judgement and social cognition. Like the accentuation processes which underpin them, it is proposed that stereotypes are sensitive to comparative context and that they reflect veridically the social self-categorical properties of stimuli.  相似文献   
99.
A model of cognitive and affective antecedents and consequences of personal goals, which integrates constructs from social-cognitive and attribution theories, was examined. Data were gathered before and after course examinations in a large university class. Hierarchical and moderated regression analyses supported the model indicating that (1) relationships between self-efficacy, goals, and performance were positive during repeated trials over 4 1/2 months in a naturally occurring setting; (2) the stability dimension of causal attributions moderated the relationship between goal-performance discrepancies and self-efficacy; and (3) the locus of causality dimension of causal attributions moderated the relationship between goal-performance discrepancies and affective responses.We thank Susan Ashford, Jim Austin, Donald Fedor, Ruth Kanfer, Edwin Locke, Paul Nystrom, Donna Randall, Christina Shalley, Masoud Yasai-Ardekani and two anonymous reviewers for their helpful comments on earlier versions of this article. We also thank Eric Dietenberger for his help with graphics.  相似文献   
100.
John Heil 《Topoi》1992,11(1):103-110
I am grateful to John Bickle, Jaegwon Kim, Brian McLaughlin, and, most especially, to my colleague, Alfred Mele, for much helpful discussion on the topic of intentional causation.  相似文献   
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