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51.
A model is presented for item responses when different subjects employ different strategies, but only responses, not choice of strategy, can be observed. Using substantive theory to differentiate the likelihoods of response vectors under a fixed set of strategies, we model response probabilities in terms of item parameters for each strategy, proportions of subjects employing each strategy, and distributions of subject proficiency within strategies. The probabilities that an individual subject employed the various strategies can then be obtained, along with a conditional estimate of proficiency under each. A conceptual example discusses response strategies for spatial rotation tasks, and a numerican example resolves a population of subjects into subpopulations of valid responders and random guessers.The first author's work was supported by Contract No. N00014-85-K-0683, project designation NR 150-539, from the Cognitive Science Program, Cognitive and Neural Sciences Division, Office of Naval Research. We are grateful to Murray Aitkin, Isaac Bejar, Neil Dorans, Frederiksen, and Marklyn Wingersky for their comments and suggestions, and to Alison Gooding, Maxine Kingston, Donna Lembeck, Joling Liang, and Kentaro Yamamoto for their assistance with Example 2. 相似文献
52.
Relation algebras from cylindric and polyadic algebras 总被引:1,自引:0,他引:1
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54.
This paper is a reply to an accompanying set of six commentaries by Sidman; Hayes and Barnes; Schusterman, Kastak, and Reichmuth; Tonneau and Sokolowski; Lowenkron; and Moerk. Those commentaries were prompted by our article “On the Origins of Naming and Other Symbolic Behavior” (1996), which was, in turn, followed by 26 commentaries and a reply. In the course of the present reply, we further develop the naming account to embrace more complex verbal relations such as same, different, more, and less. We also examine what we see as the lack of conceptual coherence in equivalence theories, including relational frame theory, and the disparities between these accounts and the findings from empirical research. 相似文献
55.
Math J. J. M. Candel 《Psychometrika》1997,62(1):119-131
Arrangements of feature sets that have been proposed to represent qualitative and quantitative variation among objects are shown to generate identical sets of set-symmetric distances. The set-symmetric distances for these feature arrangements can be represented by path lengths in an additive linear tree. Imperfect versions of these feature arrangements are proposed, which also are indistinguishable by the set-symmetric distance model. The distances for the imperfect versions can be represented by path lengths in an additive imperfectly linear tree. When dissimilarities are defined by the more general contrast model and a constant may be added to proximity data, then for both the perfect and imperfect arrangements an additive tree analysis obtains a perfect fit with an imperfectly linear tree. However, in the case of the contrast model also the distinction between the perfect and imperfect arrangements disappears in that also for the perfect arrangements the resulting tree need no longer be linear.The author is grateful to Mathieu Koppen for detailed comments on an earlier version of this article. 相似文献
56.
In this paper we address the problem of combining a logic with nonmonotonic modal logic. In particular we study the intuitionistic case. We start from a formal analysis of the notion of intuitionistic consistency via the sequent calculus. The epistemic operator M is interpreted as the consistency operator of intuitionistic logic by introducing intuitionistic stable sets. On the basis of a bimodal structure we also provide a semantics for intuitionistic stable sets. 相似文献
57.
In the area of child psychosocial intervention research, substantial progress in addressing challenging methodological issues has been made. In this article we suggest that continued movement forward requires maintaining a balance between methodological and theoretical issues, and that it would be advantageous to begin to think about matching advances in methodological sophistication by similar advances in theoretical sophistication. The need to advance our understanding of theoretical issues is especially important in light of the challenges raised by postmodernism, particularly as these challenges relate to knowledge development. We discuss these challenges and describe how a pragmatic orientation may be a useful way to respond to them. We also describe how a pragmatic orientation has been useful in our work in developing, implementing and evaluating psychosocial interventions for children with phobic and anxiety disorders. 相似文献
58.
中国颜色体系研究 总被引:7,自引:1,他引:6
概述了用颜色立体模型表示物体颜色,并做定量表示的颜色体系研究的理论意义及应用价值。介绍了国际上影响较大的颜色体系理论和编制原则的特点。中国颜色体系研究是在对国际上其它颜色体系的理论分析和对颜色样品测试的基础上,确立其理论依据和编制原则,开展了中国人眼对明度、色调、彩度等间距排列的视觉评价实验,建立了中国颜色体系理论模型。同时研制出《中国颜色体系样册》。该项研究于1993年7月通过了国家自然科学基金委员会和中国科学院联合召开的成果鉴定会,并得到良好的评价,又于1994年6月通过国家标准审查。该项研究的完成和推广,不仅能为我国国民经济各部门的颜色控制、标定和交流提供科学的颜色定量手段,同时也是对实用色度学的发展和颜色标准化工作做了有益的工作,产生了积极的经济效益和社会效益。 相似文献
59.
60.
James E. Huchingson 《Zygon》1997,32(4):515-524
The primordial chaos of Genesis 1 may be understood as the Pandemonium Tremendum (or PT), the infinite field of variety or abundance within God. The concept of variety is taken from Claude Shannon's theory of communication. Especially significant is Shannon's notion that communication is the limitation of variety through decision processes. In one model of the divine life suggested by the theory, the PT is the boundless source of potential reaped by an agential God in the act of creation as a communication process. Other models for creation include the PT in a biased mode and creatures themselves as decision agents. 相似文献