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A new status index derived from sociometric analysis 总被引:21,自引:0,他引:21
Leo Katz 《Psychometrika》1953,18(1):39-43
For the purpose of evaluating status in a manner free from the deficiencies of popularity contest procedures, this paper presents a new method of computation which takes into accountwho chooses as well ashow many choose. It is necessary to introduce, in this connection, the concept of attenuation in influence transmitted through intermediaries.This work was done under the sponsorship of the Office of Naval Research. 相似文献
74.
Temporal pattern perception for vision and audition was measured using pair comparisons of precisely determined rhythms as test items. Visual rhythms were more difficult to match than were comparable auditory ones. Crossmodal transfer equaled intramodal transfer in one experiment but was inferior in another. The differences between intra- and crossmodal transfer were related to the frequency of pattern elements, with crossmodal performance decreasing more when frequency rose. The nine test items showed a consistency in relative difficulty across experimental conditions. Differences in item difficulty were related to the symmetry of the first pattern in the item. 相似文献
75.
Strength of scopolamine-induced amnesia as a function of time between training and testing 总被引:1,自引:0,他引:1
Variations in the strength of scopolamine-induced amnesia as a function of age of the habit were studied in Swiss Webster mice. Animals were trained in an active avoidance task to a criterion of 9/10 avoidances and immediately following training injected with scopolamine hydrochloride (1.0 mg/kg) or saline. Retention of the avoidance learning was evaluated by testing different groups of animals 1, 3, 7, 10, 14, and 28 days following training. The retention test consisted of five trials in which the CS but not the UCS was presented. Results indicated that saline-treated mice exhibited near-perfect retention up to 14 days post-training with forgetting beginning to be apparent at 28 days. Scopolamine treatment produced strong amnesia in animals tested 1 and 3 days post-training but normal retention in animals tested 7 and 10 days after learning. The amnesia abruptly reappeared at 14 days after which time it remained stable. The marked similarity of the scopolamine retention curve to changes in the strength of memory of discrimination learning in undertrained rats reported by Deutsch suggested that scopolamine resulted in the storage of a weak memory of the avoidance response. To explore this idea further we trained mice to a criterion (4/5) which would result in a weak avoidance response and tested different groups 1, 3, 10, 14, and 28 days following learning. Results showed that strength of the memory of avoidance learning increased up to 10 days and then decreased abruptly at 14 days thus replicating the general shape of the retention curve produced by injecting scopolamine following strong training. These data suggest that scopolamine disrupts processes essential for the formation of durable memories. 相似文献
76.
Through a one-year internship, counselors develop attitudes and competencies needed to promote the career development of handicapped high school students. This new specialty in the counseling field, although it incorporates elements of rehabilitation, school, and vocational counseling, occurs within the framework of special education classes in regular high schools, and therefore is markedly different from any existing specialty. The role model developed in this project, now in its fifth year, stresses outreach, planning, and an active part for the counselor. This approach has been found effective both with handicapped and with learning disabled students in several urban schools. 相似文献
77.
Miguel A. García-Pérez 《Behavior research methods》1987,19(1):42-46
In this paper, we present a BASIC program for Apple II series computers that allows the user to obtain perspective drawings of two-dimensional functions of known analytical expression. Also, we outline a procedure for obtaining perspective representations of two-dimensional arrays of data using the same program. The program should run on any computer with graphics mode with only slight modifications in the graphics commands. 相似文献
78.
Francisco Flores 《国际科学哲学研究》1999,13(2):123-134
In this paper I draw on Einstein's distinction between “principle” and “constructive” theories to isolate two levels of physical theory that can be found in both classical and (special) relativistic physics. I then argue that when we focus on theoretical explanations in physics, i.e. explanations of physical laws, the two leading views on explanation, Salmon's “bottom‐up” view and Kitcher's “top‐down” view, accurately describe theoretical explanations for a given level of theory. I arrive at this conclusion through an analysis of explanations of mass—energy equivalence in special relativity. 相似文献
79.
The present research investigated in a dual task design the effects of extraversion level and structural task properties on the recall of an incidentally learned text. First, the hypothetical relation between arousal level and attentional selectivity was tested. Second, the relation between structural levels in the text and recall of text elements was studied. It was found that (a) extraverts performed significantly better on incidental recall compared to introverts; (b) the nuclear sentences at the top of the hierarchical structure were the best recalled sentences, independently of arousal level; (c) the effect of differences in arousal on recall was only significant in case of the top sentences. The effect was absent in case of specificúsecondary sentences. 相似文献
80.
The pronunciation of the same word may vary considerably as a consequence of its context. The Dutch word tuin (English, garden) may be pronounced tuim if followed by bank (English, bench), but not if followed by stoel (English, chair). In a series of four experiments, we examined how Dutch listeners cope with this context sensitivity in their native language. A first word identification experiment showed that the perception of a word-final nasal depends on the subsequent context. Viable assimilations, but not unviable assimilations, were often confused perceptually with canonical word forms in a word identification task. Two control experiments ruled out the possibility that this effect was caused by perceptual masking or was influenced by lexical top-down effects. A passive-listening study in which electrophysiological measurements were used showed that only unviable, but not viable, phonological changes elicited a significant mismatch negativity. The results indicate that phonological assimilations are dealt with by an early prelexical mechanism. 相似文献