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221.
Pigeons were trained on a multiple schedule of reinforcement in which separate concurrent schedules occurred in each of two components. Key pecking was reinforced with milo. During one component, a variable-interval 40-s schedule was concurrent with a variable-interval 20-s schedule; during the other component, a variable-interval 40-s schedule was concurrent with a variable-interval 80-s schedule. During probe tests, the stimuli correlated with the two variable-interval 40-s schedules were presented simultaneously to assess preference, measured by the relative response rates to the two stimuli. In Experiment 1, the concurrently available variable-interval 20-s schedule operated normally; that is, reinforcer availability was not signaled. Following this baseline training, relative response rate during the probes favored the variable-interval 40-s alternative that had been paired with the lower valued schedule (i.e., with the variable-interval 80-s schedule). In Experiment 2, a signal for reinforcer availability was added to the high-value alternative (i.e., to the variable-interval 20-s schedule), thus reducing the rate of key pecking maintained by that schedule but leaving the reinforcement rate unchanged. Following that baseline training, relative response rates during probes favored the variable-interval 40-s alternative that had been paired with the higher valued schedule. The reversal in the pattern of preference implies that the pattern of changeover behavior established during training, and not reinforcement rate, determined the preference patterns obtained on the probe tests. 相似文献
222.
Electrodermal lability in anxiety disorders 总被引:1,自引:0,他引:1
HANS HENRIK JENSEN NICOLAS HASLE MORTEN BIRKET-SMITH 《Scandinavian journal of psychology》1996,37(1):103-108
Twenty-eight anxiety patients, aged below 50 years, were diagnosed according to DSM-III-R criteria (panic disorder with and without agoraphobia, generalised anxiety disorder, and anxiety disorder not otherwise specified). The patients were characterised by high levels of state and trait anxiety and neuroticism, compared with the controls. However, there were no differences between patients and controls in electrodermal habituation rate, non-specific activity, or skin resistance level. When the patients were divided into electrodermally labile and stable subjects, significant differences were found between patients and controls in both electrodermal activity and Eysenck's personality dimensions. The labile patients were more introverted and attained higher psychoticism scores than either the stable patients or controls. Duration of anxiety symptoms removed the difference found in extroversion, but not in any other variable. The results are discussed in relation to the utility of electrodermal measurements in validation of diagnostic entities. It is concluded, that from the psychophysiological point of view, anxiety disorders may be examined within a dimensional framework. 相似文献
223.
Decompositions and biplots in three-way correspondence analysis 总被引:1,自引:0,他引:1
In this paper correspondence analysis for three-way contingency tables is presented using three-way generalisations of the singular value decomposition. It is shown that in combination with Lancaster's (1951) additive decomposition of interactions in three-way tables, a detailed analysis is possible of the deviations from independence. Finally, biplots are shown to produce powerful graphical representations of the results from three-way correspondence analyses. An example from child development is used to illustrate the theoretical developments. 相似文献
224.
We investigate under what conditions contrary-to-duty (CTD) structures lacking temporal and action elements can be given a coherent reading. We argue, contrary to some recent proposals, that CTD is not an instance of defeasible reasoning, and that methods of nonmonotonic logics are inadequate since they are unable to distinguish between defeasibility and violation of primary obligations. We propose a semantic framework based on the idea that primary and CTD obligations are obligations of different kinds: a CTD obligation pertains to, or pre-supposes, a certain context in which a primary obligation is already violated. This framework is presented initially as an extension of Standard Deontic Logic (SDL), a normal modal logic of type KD, and is illustrated by application to a series of examples. The concluding section is concerned with some resemblances between CTD and defeasible reasoning. We show first that the SDL-based framework contains a flaw and must be adjusted. A discussion of possible adjustments, including an alternative treatment in terms of a preference-based semantics, reveals difficulties that are reminiscent of problems in defeasible reasoning and intensional accounts of defeasible conditionals. 相似文献
225.
Wilna A. J. Meijer 《Studies in Philosophy and Education》1996,15(1-2):113-120
The issue of this paper is cultural plurality as a problem for public, general education and for (personal) identity. In order to examine this question, one needs to be clear about the meaning of the concepts of general education, on the one hand, and cultural diversity on the other. In the first section, we will fix the meaning of these concepts. A conceptual distinction between cultural diversity and cultural pluralism will be introduced. In the second section, it will be argued that open pluralism can only be maintained if there is a basic common culture apart from the cultural diversity that pluralism affirms. Therefore, there is yet an indispensable role for general education in an open, pluralistic society. In the third section we will look at two metaphors that give an opposite significance to the relation between identity and diversity: the conversational metaphor and the food metaphor mishmash. The final section expands on the conversational metaphor by way of an exposition of Ricoeur's hermeneutics of the self. It supplies us with a promising concept of identity that is not in complete opposition to diversity. 相似文献
226.
C. J. B. Macmillan 《Studies in Philosophy and Education》1996,15(1-2):77-88
In responding to and examining Mary Anne Raywid's (1989) adoption of community building as an aim for schools, I survey a number of types of communities, including recreational, intentional and language communities. In considering all these communities, I try to show both the power of communities in our personal lives and some idea of why we might be of two minds about promoting community as an ideal in the modern world and in schools in particular. 相似文献
227.
Harald Wohlrapp 《Argumentation》1998,12(3):341-350
228.
Three psychological theories of psychosis are described, each of which has standing in psychiatry. Defined by the terms projection, double bind, and possession, they initially appear to have little or nothing in common to explain psychosis, but converge at four points: (1) A high degree of anxiety precipitated by a dilemma or conflict perceived to be unsolvable by the person; (2) the anxiety triggers a shift from one thought or motive in the direction of its opposite, because the original was believed too antagonistic to the wishes of significant others; (3) the opposite, in order to remain opposite, requires that the original thought or motive be forgotten, (4) a singular means to produce and reinforce forgetting is the interposition of psychiatric symptoms. In psychiatry today treatment would fit more consistently with the three theories taken as a whole rather than any one, and a rationale for this viewpoint is elaborated. 相似文献
229.
Michele A. Craft Sheila R. Alber William L. Heward 《Journal of applied behavior analysis》1998,31(3):399-415
Four fourth graders with developmental disabilities were trained to recruit teacher attention while they worked on spelling assignments in a general education classroom. The students were taught to show their work to the teacher two to three times per session and to make statements such as, “How am I doing?” or “Look, I'm all finished!” Training was conducted in the special education classroom and consisted of modeling, role playing, error correction, and praise. A multiple baseline across students design showed that recruitment training increased (a) the frequency of students' recruiting, (b) the frequency of teacher praise received by the students, (c) the percentage of worksheet items completed, and (d) the accuracy with which the students completed the spelling assignments. 相似文献
230.
Rudolf H. Moos 《American journal of community psychology》1996,24(1):193-201
The contributions to this Special Issue illustrate research on several important types of environmental units, including psychiatric and substance abuse treatment programs, neighborhood block groups, and entire communities. They also exemplify alternative methodologies, such as assessing environments by relying on participants' appraisals, external observers' ratings, historical archives, and direct observation. I draw on these contributions and some of my own work to discuss four recurrent issues: (a) how to conceptualize environmental domains and dimensions; (b) how to understand environmental dynamics, that is, the interplay of environmental factors both within one setting and across settings; (c) how to comprehend the processes that link environmental factors to outcomes, especially with respect to the power and evanescence of environmental influence; and (d) how to use information about environments to monitor and improve them. Increased knowledge in these four areas is essential to help fulfill a major aim of community psychology: to understand social processes and improve intervention program outcomes. 相似文献