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931.
932.
Four least-squares methods for constructing factor scores have been described in the literature. The formal properties of these scores are developed, and they are compared in terms of four generally desirable properties of constructed factor scores. In particular, it is shown that two of the methods yield scores that are conditionally unbiassed, and univocal in the sense of Guilford and Michael, though not orthogonal, while one of the other methods yields orthogonal scores.It is shown that constructed factor scores cannot be simultaneously univocal and orthogonal, unless we choose the special basis in factor space given by Canonical Factor Analysis.The general problem of choosing between the methods is discussed, on the basis of the theoretical relations obtained.EDITOR'S NOTE: The reader will quickly discover that this article develops several of the generalizations given in the second part of the preceding article, On Factors and Factor Scores. Independent development of the same generalizations is, of course, not a new phenomenon. Because the Presidential Address automatically is accepted for publication and given space in the December issue, it was decided that the only fair thing to do was to print this article in the same issue.  相似文献   
933.
Asymptotic behavior: the concept of the operant   总被引:2,自引:0,他引:2  
  相似文献   
934.
935.
The author holds the opinion that the so-called operant, or instrumental, conditional reflexes, in spite of differences in specific features, do not differ in principle from classical conditional reflexes, and therefore they should not be opposed to them, or be placed in a special or separate group. In support of this opinion, this paper presents data which show that:
  1. 1.
    In the establishment of classical and operant conditional reflexes, two-way conditional connections—direct and reverse—are formed.  相似文献   
936.
In this paper we concern ourselves with the problem of whether or not conditioning stimuli of other modalities or stimuli applied to a distant locus of the body interact with a sensitive test of somesthetic temporal acuity we have called the gap test. The results of the experiment indicate that visual stimuli do not exert an observable influence on this temporal judgment, but that auditory stimuli and contralateral stimulation in the same modality do show a significant but relatively small effect. This is compared and contrasted with the very large and persistent effect reported when the conditioning stimulus is applied to the same electrodes as the gap test. By comparing our results with experiments of similar design carried out on lower animals by other investigators, some insights into the neural localization of the reported effects is obtained.  相似文献   
937.
Early work on the Müller-Lyer illusion had indicated that it disappears with extended practice. The present experiment failed to confirm this finding. The magnitude of the illusion decreased for approximately 500 trials, but showed no further change over an additional 500 trials. The rate of the practice decrement was inversely related to the size of the angle formed by the oblique lines of the figure.  相似文献   
938.
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   
939.
If S. S. Stevens’ exponents indicate the rates at which sensations grow with increases in sensory intensity, they ought to correlate with the population norms of top sensory magnitudes. Using a comprehensive sample of eight sensory dimensions, the tau coefficient of rank correlation between Stevens’ exponents and the medians of the top sensory magnitudes reported by 305 observers was found to be only +.15 (p>05). With the geometric means tau fell to ?.04. A split-half consistency check on the medians of the population norms suggested that they were not to blame for the low correlation. Direct comparisons of pairs of sensory dimensions on 146 additional observers produced results which confirmed the population norms. Since there is no way of comparing most of the top physical stimuli experienced in everyday life, it is not possible to make a joint prediction from exponents and top stimuli. S. S. Stevens’ exponents thus appear to have little predictive value outside the experimental conditions under which they were measured.  相似文献   
940.
R asmussen , E. T ranekjær . Bridging physiology and phenomenology in dynamic psychology. Scand. J. Psychol ., 1961, 2, 161–166.—It is important to distinguish between the immediately experienced (the phenomenological) and the physiological-neurological basis for the phenomenological world, e.g. between beta needs (subjectively experienced states of needing or wanting) and alpha needs (objectively defined, physiological needs). The concept of psychon is introduced and defined as a necessary and sufficient condition in the physiological-neurological system for the existence of a subjective experience; psychon bridges the gap between the physiological and the phenomenological world.  相似文献   
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