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1.
Analysis of the carbon disulphide extracts of nine samples of UK coal-maceral concentrates by 1H highresolution n.m.r. spectroscopy, gas-liquid chromatography and field-desorption mass spectrometry indicates the presence of components with a wide molecular weight range extending up to 1200 amu; these are attributed to n-alkanes up to ≈C50 and highly condensed polynuclear aromatic compounds. 相似文献
2.
Linda A. Jackson Edward A. Witt Alexander Ivan Games Hiram E. Fitzgerald Alexander von Eye Yong Zhao 《Computers in human behavior》2012
This research examined relationships between children’s information technology (IT) use and their creativity. Four types of information technology were considered: computer use, Internet use, videogame playing and cell phone use. A multidimensional measure of creativity was developed based on and test of creative thinking. Participants were 491 12-year olds; 53% were female, 34% were African American and 66% were Caucasian American. Results indicated that videogame playing predicted of all measures of creativity. Regardless of gender or race, greater videogame playing was associated with greater creativity. Type of videogame (e.g., violent, interpersonal) was unrelated to videogame effects on creativity. Gender but not race differences were obtained in the amount and type of videogame playing, but not in creativity. Implications of the findings for future research to test the causal relationship between videogame playing and creativity and to identify mediator and moderator variables are discussed. 相似文献
3.
The stress inoculation (SI) paradigm, which consists of education (ED), coping skills training (CST), and exposure to simulated stressors (EX), was applied to the occupational stress experienced by nurses. Occupational stress was operationally defined in terms of 13 dependent measures reflecting problem areas summarized by the acronym ReACT (retrograde complaints, assertiveness deficits, competency concerns, and time stress). ReACT also stood for the ingredients of the CST component (relaxation training, assertive skill building, cognitive restructuring, and time management instruction). To determine which SI components produce a treatment effect, 60 White female acute-care registered nurses (mean age 33.8 yrs) were randomly assigned to 1 of 4 active treatment cells: SI, CST, EX, ED, or no treatment (NT). Ss were administered a battery of tests that included the State–Trait Anxiety Inventory and Rathus Assertiveness Schedule. A MANOVA at posttest, and subsequent univariate analyses simultaneously considering 4-mo follow-up data, demonstrated that SI is an effective treatment with durable benefits and that CST is its principal ingredient. Additional demand-characteristics analyses indicated that these effects are not due to placebo-related phenomena. (54 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
Criticizes the D. W. Levine and W. P. Dunlap (see record 1983-24833-001) rejoinder to the present author's (see record 1983-20171-001) article on curvilinear transformation of the dependent variable. Levine and Dunlap's (1983) claims are based on a failure to distinguish theoretical models from empirical data and a misconception about implications from the fact that the t test is a uniformly most powerful unbiased test. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
Richard A. Games 《Algorithmica》1986,1(1):233-250
This paper gives 3-page book embeddings of three important interconnection networks: the FFT network, the Benes rearrangeable permutation network, and the barrel shifter network. Since all three networks are eventually nonplanar, they require three pages and the present embeddings are optimal. Also, the embeddings have pages of comparable widths.The embeddings of the FFT and barrel shifter networks are obtained by decomposing these recursively defined networks into smaller copies of themselves and using induction. The embedding of the Benes network uses a novel decomposition of the network into eight copies of a smaller FFT network.This work was accomplished as a part of the MITRE Corporation's Independent Research and Development Program. 相似文献
6.
The author, who is an artist and designer, has invented a process of copying on to unsensitized surfaces by selective distillation. 相似文献
7.
D. W. Levine and W. P. Dunlap (see record 1982-27158-001) concluded that tests on skewed data lack power. The present author contends that this conclusion is incorrect. What they have rediscovered is that curvilinear transformations change population means and population variances, as well as the form (skewness and kurtosis) of the population. Thus, such transformations change the noncentrality parameter, φ. When the null hypothesis is false, the power entries in the rows of their Table 1 are influenced by all of these characteristics. To attribute this change to skewness alone is incorrect. Many distinctions are pertinent to the choice of whether to use such transformations: informal data analysis vs formal inference on experiments based on strong theory, the size of the error term relative to the size of the treatment effects, considerations of interactions, simplicity of results, and statistical assumptions. Skewness is the least important of these factors. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
Pairwise multiple comparison procedures (MCPs) are appropriate when the behavioral researcher is interested in comparing all possible pairwise mean differences. An exposition of the various simultaneous MCPs is presented that classifies those procedures as either (a) nonrobust to combinations of variance heterogeneity and unequal sample sizes because a pooled within-cell estimate of error variability is used to obtain the standard error of the contrast; or (b) robust to the homogeneity assumption because the standard error of the contrast is obtained via the Behrens-Fisher solution, and various approximate and/or conservative critical values that maintain the overall level of Type I error at "alpha" are used. A numerical example illustrating the latter MCPs is given. A choice among P. A. Games and J. F. Howell's (1976), C. W. Dunnett's (1980), and W. G. Cochran's (1964) procedures is recommended. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
A prior article by P. A. Games (1978) presented numerous statistical hypothesis-testing procedures for independent groups. These resulted from crossing 3 factors: technique used, method of control of Type 1 errors, and parameter used. Tests on means, correlations, proportions, and variances are represented by using θ for the parameter, and θ? for the statistic. The prior article was limited to cases in which the variance of the statistic V k(θ) was a constant and hence was limited to equal ns. The present article contains the extention to unequal V k(θ?) cases and hence permits unequal ns. More general large-sample forms of the t and F statistics, namely, the t′ and the df uF′ statistics, are recommended for the unequal V k(θ?) cases. The B. L. Welch solution for general contrasts on means is presented as a minor adaptation of t′. The Welch solution for an omnibus test on means is a minor adaptation of df uF′. Examples are given that illustrate the application of t′ and df uF′. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
Richard A. Games 《Algorithmica》1986,1(1-4):233-250
This paper gives 3-page book embeddings of three important interconnection networks: the FFT network, the Benes rearrangeable permutation network, and the barrel shifter network. Since all three networks are eventually nonplanar, they require three pages and the present embeddings are optimal. Also, the embeddings have pages of comparable widths. The embeddings of the FFT and barrel shifter networks are obtained by decomposing these recursively defined networks into smaller copies of themselves and using induction. The embedding of the Benes network uses a novel decomposition of the network into eight copies of a smaller FFT network. 相似文献