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111.
A modification of the TUCKALS3 algorithm is proposed that handles three-way arrays of order I × J × K for any I. When I is much larger than JK, the modified algorithm needs less work space to store the data during the iterative part of the algorithm than does the original algorithm. Because of this and the additional feature that execution speed is higher, the modified algorithm is highly suitable for use on personal computers. This research has been made possible by a fellowship from the Royal Netherlands Academy of Arts and Sciences to the first author.  相似文献   
112.
Ingram Olkin 《Psychometrika》1981,46(4):469-472
It is well-known that for a trivariate distribution if two correlations are fixed the remaining one is constrained. Indeed, if one correlation is fixed, then the remaining two are constrained. Both results are extended to the case of a multivariate distribution. The results are applied to some special patterned matrices.  相似文献   
113.
For a fixed set of standardized regression coefficients and a fixed coefficient of determination (R-squared), an infinite number of predictor correlation matrices will satisfy the implied quadratic form. I call such matrices fungible correlation matrices. In this article, I describe an algorithm for generating positive definite (PD), positive semidefinite (PSD), or indefinite (ID) fungible correlation matrices that have a random or fixed smallest eigenvalue. The underlying equations of this algorithm are reviewed from both algebraic and geometric perspectives. Two simulation studies illustrate that fungible correlation matrices can be profitably used in Monte Carlo research. The first study uses PD fungible correlation matrices to compare penalized regression algorithms. The second study uses ID fungible correlation matrices to compare matrix-smoothing algorithms. R code for generating fungible correlation matrices is presented in the supplemental materials.  相似文献   
114.
The clinical differentiation of progressive supranuclear palsy from Parkinson's disease can be challenging, due to overlapping clinical features and a lack of diagnostic markers. Abnormalities in cognitive function form part of the clinical spectrums of these diseases and distinctive cognitive profiles may be helpful in differentiating these diseases in the diagnostic period. A comprehensive neuropsychological test battery was administered to 12 patients with clinically diagnosed progressive supranuclear palsy and 12 patients with Parkinson's disease matched for age and disease duration. Effect size (Cohen's d) was calculated for cognitive tests that were significantly different between groups. Patients with progressive supranuclear palsy performed significantly worse than those with Parkinson's disease on measures of processing speed, verbal fluency, planning, verbal abstract reasoning, verbal memory, and made more perseverative responses on a set shifting task. Measures of executive function, manual dexterity and processing speed were most diagnostically useful (Cohen's d > 2.0) in differentiating between progressive supranuclear palsy and Parkinson's disease. These findings suggest that more severe and prominent ‘frontal’ cognitive deficits in patients with progressive parkinsonism would be helpful in predicting progressive supranuclear palsy rather than Parkinson's disease and these findings may contribute to the development of diagnostic criteria.  相似文献   
115.
Engineering science is a scientific discipline that from the point of view of epistemology and the philosophy of science has been somewhat neglected. When engineering science was under philosophical scrutiny it often just involved the question of whether engineering is a spin-off of pure and applied science and their methods. We, however, hold that engineering is a science governed by its own epistemology, methodology and ontology. This point is systematically argued by comparing the different sciences with respect to a particular set of characterization criteria. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
116.
We tested whether level and/or changes in inspection time (IT) in an elderly sample (70–85 years at baseline) predicted future independence in everyday functioning, independent from chronological age. Sixty-eight participants were initially assessed on IT and cognitive abilities in 2003, reassessed on IT in 2005, and then completed the Everyday Problems Test, a test of independence in everyday living, in 2008. Controlling for age, lower fluid reasoning at baseline (Raven’s-subset) and slowing IT over 18 months independently predicted poorer everyday functioning in 2008, together accounting for one-third variance. This supports the proposition that IT has utility as a biomarker for less favourable ageing.  相似文献   
117.
Increasing and new work demands drain employees’ energy resources at work. This 4-week longitudinal field experiment investigated the energizing potential of a respite intervention conducted at the workplace (either a simulated savouring nature intervention or a progressive muscle relaxation intervention). First, growth modelling analyses confirmed a linear trend for the growth of vigour and decline in fatigue across the days of the intervention group, indicating a typical upward resource trajectory. No changes appeared in the control group. Mediation analyses indicated that repeatedly engaging in a daily respite intervention influenced more stable energy levels after the intervention period indirectly through the immediate changes in daily energy levels during the intervention period. Findings suggest that, in some cases, respite interventions may present a useful tool to replenish and build energy resources at work. Implications for using respite intervention in organizational research and practice are discussed.  相似文献   
118.
Previous research has suggested that the availability of high-preference stimuli may override the reinforcing efficacy of concurrently available low-preference stimuli under relatively low schedule requirements (e.g., fixed-ratio 1 schedule). It is unknown if similar effects would be obtained under higher schedule requirements. Thus, the current study compared high-preference and low-preference reinforcers under progressively increasing schedule requirements. Results for 3 of the 4 participants indicated that high-preference stimuli maintained responding under higher schedule requirements relative to low-preference stimuli. For 1 participant, high-preference and low-preference stimuli were demonstrated to be equally effective reinforcers under increasing schedule requirements. Implications with respect to rate of performance and response patterns are discussed.  相似文献   
119.
Asperger's disorder is one of autistic spectrum disorders; sharing clinical features with autism, but without developmental delay in language acquisition. There have been some studies of intellectual functioning in autism so far, but very few in Asperger's disorder. In the present study, we investigated abstract reasoning ability, whose form of intelligence has been labeled fluid intelligence in the theory of Cattell [Cattell, R. B. (1963). Theory of fluid and crystallized intelligence: A critical experiment. Journal of Educational Psychology, 54, 1-22.], in children with Asperger's disorder. A test of fluid intelligence, the Raven's Standard Progressive Matrices Test, was administered to 17 children with Asperger's disorder and 17 age-, gender-, and FIQ-matched normal children. The results showed that children with Asperger's disorder outperformed on the test of fluid reasoning than typically developing children. We suggest that individuals with Asperger's disorder have higher fluid reasoning ability than normal individuals, highlighting superior fluid intelligence.  相似文献   
120.
不同病期肿瘤患者的治疗选择   总被引:1,自引:1,他引:0  
肿瘤从早期到晚期,需要选择不同的治疗手段来达到不同的治疗目的。从早期的根治性治疗到晚期的支持性治疗,随着肿瘤进展,抗肿瘤治疗强度从弱到强,到晚期又减弱。从能保证病人的生存质量到仅能减轻病人的癌性痛苦。这是肿瘤矛盾转化的必然结果,是抗肿瘤治疗的正确选择。  相似文献   
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