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291.
Correspondence analysis used complementary to loglinear analysis   总被引:1,自引:0,他引:1  
Loglinear analysis and correspondence analysis provide us with two different methods for the decomposition of contingency tables. In this paper we will show that there are cases in which these two techniques can be used complementary to each other. More specifically, we will show that often correspondence analysis can be viewed as providing a decomposition of the difference between two matrices, each following a specific loglinear model. Therefore, in these cases the correspondence analysis solution can be interpreted in terms of the difference between these loglinear models. A generalization of correspondence analysis, recently proposed by Escofier, will also be discussed. With this decomposition, which includes classical correspondence analysis as a special case, it is possible to use correspondence analysis complementary to loglinear analysis in more instances than those described for classical correspondence analysis. In this context correspondence analysis is used for the decomposition of the residuals of specific restricted loglinear models.  相似文献   
292.
A common criticism of iterative least squares estimates of communality is that method of initial estimation may influence stabilized values. As little systematic research on this topic has been performed, the criticism appears to be based on cumulated experience with empirical data sets. In the present paper, two studies are reported in which four types of initial estimate (unities, squared multiple correlations, highestr, and zeroes) and four levels of convergence criterion were employed using four widely available computer packages (BMDP, SAS, SPSS, and SOUPAC). The results suggest that initial estimates have no effect on stabilized communality estimates when a stringent criterion for convergence is used, whereas initial estimates appear to affect stabilized values employing rather gross convergence criteria. There were no differences among the four computer packages for matrices without Heywood cases.  相似文献   
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294.
Plasma concentrations of imipramine and amitriptyline and their desmethylated metabolites were measured in 20 children being treated for major depressive illness 2 wk. and 5 to 10 wk. after achieving drug dosages of 2.25 mg/kg body weight. At 2 wk. all children had exhibited clinical improvement, but by 10 wk. 4 of the 10 children treated with imipramine and 5 of the 10 children treated with amitriptyline had experienced clinical relapse of depressive symptoms. Tricyclic antidepressant plasma concentrations and ratios were comparable in the subgroups of children who maintained their clinical improvement and those who relapsed. There was no evidence of a systematic decline in plasma tricyclic antidepressant concentrations in those children who relapsed.  相似文献   
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The author diagnoses 350 carefully selected schizophrenic subjects, their parents and their siblings during parallel studies using three different clinical classification systems and analyzes the results by multiple threshold analysis and the multifactorial inheritance model. The results suggest that, of the three classifications the author studied, Leonhard's and Sneshnewski's system yield relatively homogeneous subgroups; this indicates the future significance of these nosological systems for the planning of biopsychiatric research.  相似文献   
298.
40 women were taught to use self-statements to cope with pain caused by ice water. The trainer used four different strategies for reassigning a homework task of using self-statements to cope with pain produced by immersing one hand in ice water. The strategies were equally effective in eliciting compliance with the homework assignment.  相似文献   
299.
On the basis of the hypothesis of misapplied constancy scaling, the perception of an abstract horizontal-vertical illusion figure embedded in photographs of natural scenes with depth cues is investigated. The effect is compared with that of a figure on photographs containing no depth information and with a figure on a neutral surface. It is shown that the magnitude of the illusion in the perspective scenes is greater than in the other two conditions. The results are considered compatible with a constancy theory of the illusion. Finally, the evidence for misapplied constancy scaling in the horizontal-vertical illusion in relation to a retinal theory is discussed.  相似文献   
300.
Improvement in auditory-successive selective attention was noted across the age range of 9 through 16 yr. In contrast to comparable paradigms with visual-simultaneous materials, 30 learning disabled and 30 normal boys did not differ. Results of research on selective attention may be affected by task materials and encoding requirements.  相似文献   
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