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11.
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   
12.
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   
13.
Popper's critical rationalism is widely accepted under scientists and philosophers of science as a proper method for the reconstruction of scientific theories. On occasion of the application of the Popperian ideas for the reconstruction of chemistry by Akeroyd the flaws of the critical rationalist approach are criticised and a methodical alternative is proposed, involving the operational definition of scientific terms. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
14.
内部分配改革的职务评价技术探新   总被引:4,自引:0,他引:4  
建立工资标准系统的关键是确定职务工资率。职务间可比价值成分变异越大,对确定职务工资率的贡献也越大。根据以上研究设想采用方差分析方法进行职务评价。评价步骤包括:职务描述;对职务要素作主成分分析;对职务样本作聚类分析和判别分析;通过方差分析为可比价值各成分建构权重系数ωi。ωi‘满足:(1)ωi≥0;(2)Σωi=1;(3)ωi,间可直接比较;(4)ωi的大小与对应的可比价值成分变异一致。最后将职务评价值线性变换为工资率。在线性方程中配一个常数。和调节系数α以适合组织的管理约束条件。配合两个企业内部分配改革的研究结果显示了方差分析法的有效性和实用性。  相似文献   
15.
The experiments were performed on adult Wistar male rats trained to push with the forepaw on a fixed piston inside a narrow tube. It was found that after localized intracerebral injection of a cholinergic antagonist into the dorso-lateral (but not medial) neostriatum (i.e., the caudato-putamen) the behavioral performance requiring brief innate movements remained unchanged, but the performance requiring a prolonged pushing movement (> 50 msec) became disrupted. Microinjection of carbacholine (0.03-3 μ g/1 μ1) did not affect the performance of the acquired movements, whereas scopolamine (3 μ g/1 μ1) led to the significant decrease in pushing time. We conclude that changes in the state of the dorso-lateral neostriatal cholinergic system result only in disturbances of the sensory-controlled component of a complex instrumental movement. The 1994 Pavlovian Society Young Investigator Awardee was Nadezda Dubrovskaya, first author of this paper, which was presented at the annual meeting of the Pavlovian Society, July 3, 1994, in Prague, Czech Republic.  相似文献   
16.
A lack of studies which evaluate system change by tracking client outcomes is noted in the children's mental health area. This deficit may be a result of the inability of researchers to define outcomes and to draw conclusions about which measures reflect the efficacy of services and service delivery systems. This paper reviews five social validation surveys which examined children's mental health outcome measures. Based on the results of the five surveys, a model of critical behaviors and events is presented. This model will assist evaluators and researchers in understanding which critical events and behaviors should be measured to assess the impact of community-based mental health services for children.  相似文献   
17.
Results of 1,579 observations of cars entering or exiting campus parking lots showed direct relationships between seat belt wearing and the intrusiveness of the engineering device designed to induce belt usage, and between device intrusiveness and system defeat. For example, all drivers with working interlocks or unlimited buzzer reminders were wearing a seat belt; but 62% of the systems with interlocks or unlimited buzzers had been defeated, and only 15.9% of the drivers in these cars were wearing a seat belt. The normative data indicated marked ineffectiveness of the negative reinforcement contingencies implied by current seat belt inducement systems; but suggested that unlimited buzzer systems would be the optimal system currently available if contingencies were developed to discourage the disconnection and circumvention of such systems. Positive reinforcement strategies are discussed that would be quite feasible for large-scale promotion of seat belt usage.  相似文献   
18.
Interpretations regarding the effects of exogenous and endogenous variables on endogenous variables in linear structural equation systems depend upon the convergence of a matrix power series. Convergence depends upon the eigenvalues of the structural coefficient matrix. The test for convergence developed by Jöreskog and Sörbom is shown to be only sufficient, not necessary and sufficient.  相似文献   
19.
Analysis of the elements of attention: A neuropsychological approach   总被引:15,自引:0,他引:15  
A model for conceptualizing the components or elements of attention is presented. The model substitutes for the diffuse and global concept of attention a group of four processes and links them to a putative system of cerebral structures. Data in support of the model are presented; they are derived from neuropsychological test scores obtained from two samples, the first consisting of 203 adult neuropsychiatric patients and normal control subjects, and the second, an epidemiologically-based sample of 435 elementary school children. Principal components analyses of test scores from these two populations yielded similar results: a set of independent elements of attention that are assayed by different tests. This work presents a heuristic for clinical research in which the measurement of attention is essential.  相似文献   
20.
The definition and role of the expert witness is reviewed. Two conceptual systems for viewing the world, the scientific method and the adversarial system, are compared. The reconciliation and integration of these two discrepant systems are discussed in terms of input versus outcome. The rules of evidence, as well as problems of communication between the systems, are reviewed with the aim of providing expert witnesses with a better understanding of effective testimony. Finally, collaboration between the two systems is called for in order to provide guidelines for both neuropsychologists and attorneys.  相似文献   
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