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121.
Preconditioning, with a burst of electrical pulse stimuli elevates the threshold for temporal acuity as measured with a technique requiring the S to detect a short gap in an otherwise regular burst of similar stimuli. Only a small amount of backward inhibition can be observed. The temporal duration of the inhibitory effect (up to 700 msec.) suggests that repetitive after-discharges of second-order afferents in Ike spinal cord may underlie this behavioral measure by actually filling in the intervals which are used by the S to make the judgment. The phenomenon is thus thought to be a disruption of a true temporal judgment rather than one indirectly mediated by an amplitude judgment, and as such it represents a significant datum on the temporal resolving power of time dimensions of neural coding.  相似文献   
122.
A battery of 18 tests of intermediate algebra and 20 reference tests was administered to two successive second-year algebra classes. Each battery was separately factor analyzed by Thurstone methods, and the two analyses were synthesized by the Tucker method. The five congruent factors obtained were identified as: Verbal Comprehension, Deductive Reasoning, Algebraic Manipulative Skill, Number Ability, and Adaptability to a New Task.This paper is a condensation of a thesis. The work was begun while the author was a Psychometrics Fellow of the Educational Testing Service. The work was further supported by Contract N6onr-270-20 of the Office of Naval Research and by Grant NSF G-642 of the National Science Foundation. The writer is indebted to Professors Harold Gulliksen and Ledyard R Tucker for their guidance throughout this study.  相似文献   
123.
An exposition of a calculus for empirical classes (CEC), one of the few attempts by logicians to deal with the problem of constructs and indicators, is presented. The CEC provides the groundwork for a formal structure for the situation in which individuals have a degree of membership in various classes rather than having either membership or nonmembership—a situation nearly always true in empirical research. The CEC is presented and its relation to various social science concepts is mentioned. An application of the CEC model to latent structure analysis (LSA) suggests alternatives to the local independence assumption including one called the local scale assumption, which has a close relation to a Guttman scale.  相似文献   
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Monkeys were trained to release a telegraph key at the onset of a pure tone. Latency of the response was measured over a 70-db range of sound pressure (re 0.0002 dyn/cm(2)) at six frequencies (250 to 15,000 cps). Latency was found to be an inverse exponential function of intensity at all frequencies. Equal loudness was inferred from the equal latency contours which were constructed from the latency-intensity functions at each frequency. These data indicate peak auditory sensitivity for the monkey near 1000 cps. At the frequencies above and below 1000 cps consistently more sound energy was required for equal latency.  相似文献   
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Investigations of a mirror-image transfer effect in pigeons   总被引:2,自引:1,他引:1       下载免费PDF全文
In two separate experiments, pigeons trained binocularly to peck a key on which an oblique line (e.g., 60 degrees counter-clockwise rotation from horizontal) was projected yielded bi-modal angularity generalization gradients in extinction, with peaks of responding at both the training stimulus and its mirror image (in this case 120 degrees ). This mirror-image transfer effect may be analogous to an "octave effect" in auditory generalization, but Mello's finding of a mirror-image reversal transfer effect following monocular training in pigeons suggests an alternative interpretation.  相似文献   
128.
When 72 male students in a southern theological institution were compared by the manner in which they intended to fulfill their religious vocation (i.e., as missionaries, pastors, or religious education workers), a homogeneity of personality behavior was observed on each of 16 factors. The total sample, however, was reported to be substantially and significantly different from the general population on four factors. No significant difference was reported among the three groups in their need for social approval as measured by the Marlowe-Crowne SDS.  相似文献   
129.
Some previous publications have indicated that the creative skills of chemists tend to decline once they are past their thirties or early forties. These conclusions have been based on such criteria of creativity as merit ratings, citations in the literature, etc. In the present study, patent records for all 89 professional men (mostly chemists and chemical engineers) in one division of a large industrial scientific organization were analyzed to determine whether creativity as measured by the production of patentable ideas tended to decrease with age, to increase, or to remain about the same. In the statistical treatment of data both longitudinal and cross-sectional methods were used. All the results were consistent in revealing no decline in creative productivity with increase in age, and indicated instead a tendency for productivity to increase as chemists mature.  相似文献   
130.
One-hundred fifty human Ss viewed 32 patterns under neutral (N), pleasingness (P), or interestingness (l) instructional sets. An analysis of variance indicated that patterns with larger areas were viewed longer than patterns with smaller areas under all conditions; however, this effect was more pronounced under the P and I conditions than under the N condition. Patterns containing 9-sided shapes were viewed longer than those containing 3-sided shapes under the N and I conditions, while the reverse was true for the P condition.  相似文献   
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