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Robert I. Jennrich 《Psychometrika》1970,35(2):229-235
The quartimax and varimax algorithms for orthogonal rotation attempt to maximize particular simplicity criteria by a sequence of two-factor rotations. Derivations of these algorithms have been fairly complex. A simple general theory for obtaining two factor at a time algorithms for any polynomial simplicity criteria satisfying a natural symmetry condition is presented. It is shown that the degree of any symmetric criterion must be a multiple of four. A basic fourth degree algorithm, which is applicable to all symmetric fourth degree criteria, is derived and applied using a variety of criteria. When used with the quartimax and varimax criteria the algorithm is mathematically identical to the standard algorithms for these criteria. A basic eighth degree algorithm is also obtained and applied using a variety of eighth degree criteria. In general the problem of writing a basic algorithm for all symmetric criteria of any specified degree reduces to the problem of maximizing a trigonometric polynomial of degree one-fourth that of the criteria.This research was supported by the Bell Telephone Laboratories, Murray Hill, New Jersey and NIH Grant FR-3. 相似文献
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The study attempted to isolate some of the environmental conditions that controlled the self-destructive behavior of three severely retarded and psychotic children. In the extinction study subjects were placed in a room where they were allowed to hurt themselves, isolated from interpersonal contact. They eventually ceased to hurt themselves in that situation, the rate of self-destruction falling gradually over successive days. In the punishment study, subjects were administered painful electric shock contingent on the self-destructive behavior. (1) The self-destructive behavior was immediately suppressed. (2) The behavior recurred when shock was removed. (3) The suppression was selective, both across physical locales and interpersonal situations, as a function of the presence of shock. (4) Generalized effects on other, non-shock behaviors, appeared in a clinically desirable direction. Finally, a study was reported where self-destructive behavior increased when certain social attentions were given contingent upon that behavior. 相似文献
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ALLEN I. KRAUT 《Personnel Psychology》1969,22(3):281-290
T his study explores the relationship between high level managers' promotional success and two measures of intellectual ability. The Concept Mastery Test was administered to 235 middle managers and 130 higher level executives who attended advanced management training programs. The Ship Destination Test was also given to about half the trainees. Both tests are considered to discriminate well among superior individuals. Those managers who earned high scores were rated more favorably by their peers and the training staff. However, advancement in the 4 to 7 years after the training program was unrelated to test performance. 相似文献
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