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911.
Two kinds of measures of multivariate association, based on Wilks' and the Bartlett-Nanda-Pillai trace criterionV, respectively, are compared in terms of properties of the univariateR 2 which they generalize. A unified set of derivations of the properties is provided which are self-contained and not restricted to decompositions in canonical variates. One conclusion is that asymmetric index based on allows generalization of the multiplicative decomposition ofR 2 in terms of squared partial correlations, but not the additive decomposition in terms of squared semipartial correlations, while the reverse is true for anasymmetric index based onV.We are indebted to Jos M. F. ten Berge for some fruitful discussions.  相似文献   
912.
Correspondence analysis of incomplete contingency tables   总被引:1,自引:0,他引:1  
Correspondence analysis can be described as a technique which decomposes the departure from independence in a two-way contingency table. In this paper a form of correspondence analysis is proposed which decomposes the departure from the quasi-independence model. This form seems to be a good alternative to ordinary correspondence analysis in cases where the use of the latter is either impossible or not recommended, for example, in case of missing data or structural zeros. It is shown that Nora's reconstitution of order zero, a procedure well-known in the French literature, is formally identical to our correspondence analysis of incomplete tables. Therefore, reconstitution of order zero can also be interpreted as providing a decomposition of the residuals from the quasi-independence model. Furthermore, correspondence analysis of incomplete tables can be performed using existing programs for ordinary correspondence analysis.  相似文献   
913.
914.
The article deals with the case of a patient who had a partial gastrectomy and developed a vitamin B12 deficiency syndrome with anemia, myelopathy and complete loss of the senses of taste and smell. Regression of the symptoms followed liberal dosing with vitamin B12.  相似文献   
915.
916.
Adult male mice were made anosmic by intranasal flushing with a 5% zinc sulfate solution. Twelve behavioral variables were measured in treated as well as saline-irrigated control animals placed in a novel environment. The genetic underpinnings and the genotype-treatment interactions with regard to these behaviors were analyzed in a classical Mendelian cross between the inbred strains C57BL/6 and DBA/2 and in a full 4 X 4 diallel cross, replicated five times, between these strains and strains C3H/St an CPB-K. Based on the hypothesis of an evolutionary history of directional selection for a well-balanced information-processing system, one might expect directional dominance for decrease in exploration after anosmization. Although decreases were found for several behavioral phenotypes, only few and relatively unimportant genotype-treatment interactions were present. This absence of any kind of genetic variation for behavioral change after anosmization points to an extremely strong directional selection which has eliminated all less favorable alleles. The findings support the hypothesis of directional selection for an efficient olfactory information-processing system.  相似文献   
917.
In this study the mechanical output (e.g., force, contraction velocity, instantaneous power) about the ankle was measured during a jump with and without occurrence of transportation of power and pre-stretch potentiation. To examine this, a model of the m. triceps surae was used. Eleven subjects performed a maximal one-legged countermovement jump (CMJ) and a maximal one-legged jump with extended knee (EKJ). Ground reaction forces, cinematographic data and electromyograms of m. triceps surae were recorded. The power output, defined as the product of moment and angular velocity, and work done about the ankle were higher during CMJ (1404 W, 130 J) than during EKJ (852 W, 76 J). The peak moments were the same during both jumps. The model of the m. triceps surae showed that the power delivered by m. triceps surae was higher during CMJ than during EKJ, as a result of catapult-action of m. gastrocnemius tendon. The difference in work done is explained, in addition to transportation of energy, by a greater contraction range of m. soleus during CMJ. There is no reason to assume that pre-stretch potentiation plays a role in the difference in mechanical output. The results show that the mechanical output of muscles in complex movements is strongly dependent on the dynamics of the movement, and not only on its contractile capacity.  相似文献   
918.
A ROWS is a ROSE: Spelling,sound, and reading   总被引:30,自引:0,他引:30  
Skilled readers generally are assumed to make little or no use of words’ phonological features in visual word identification. Contrary to this assumption, college students’ performance in the present reading experiments showed large effects of stimulus word phonology. In Experiments 1 and 2, these subjects produced larger false positive error rates in a semantic categorization task when they responded to stimulus foils that were homophonic to category exemplars (e.g., ROWS for the category A FLOWER) than when they responded to spelling control foils. Additionally, in Experiment 2, this homophony effect was found under brief-exposure pattern-masking conditions, a result consistent with the possibility that phonology is an early source of constraint in word identification. Subjects did, however, correctly reject most homophone foils in Experiments 1 and 2. Experiment 3 investigated the source of this ability. The results of Experiment 3 suggest that subjects detected homophone impostors, such as ROWS, by verifying target foil spellings against their knowledge of the correct spellings of category exemplars, such as ROSE.  相似文献   
919.
In the present study, the role of individual response patterns in the treatment of social phobic patients was investigated. Seventy-four patients were diagnosed as social phobics. On the basis of extreme scores on a behavioral test (the Simulated Social Interaction Test) and on a cognitive measure (the Rational Behavior Inventory), the response patterns of 39 patients were analyzed, and the patients themselves were classified as either 'behavioral reactors' or 'cognitive reactors'. Half of the patients with each response pattern received a behavioral focused treatment, i.e. social skills training (SST), while the other half received a cognitive oriented treatment, i.e. rational emotive therapy (RET). Patients received group therapy in eight weekly sessions. Within-group differences showed a considerable improvement in all treatment groups. Between-group differences failed to lend support to the hypothesis that treatment that fits a response pattern (i.e. SST for behavioral reactors and RET for cognitive reactors) will result in a greater improvement than one that does not.  相似文献   
920.
Nine social phobics and 9 normal control subjects were exposed to slides of angry faces, happy faces, and neutral objects (i.e. flowers or mushrooms). Skin conductance responses (SCRs) to the stimuli and eyeblink rate (EBR) during stimulus exposure were recorded. In addition, subjects were asked to rate the stimuli in terms of pleasantness. While angry face stimuli elicited greater SCRs, stronger inhibition of EBR, and were evaluated more negatively than the other stimuli, there were no differences between social phobics and normals in these respects. Thus, the findings lend no support to the idea that social phobics are particularly sensitive to facial cues in general or to negative facial cues in particular.  相似文献   
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