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Screening methodYu, Chau-ping. January 1900 (has links)
Thesis (M.Soc.Sc.)--University of Hong Kong, 1993. / Includes bibliographical references (p. 52-54) Also available in print.
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A PARALLEL APPROACH TOWARDS CORRELATION MEASUREMENT GENE PAIRS WITH TIME-LAGGING EXPRESSION BEHAVIORSCao, Xiaopeng 01 December 2009 (has links)
Some current similarity measurement method include Normal Euclidean Distance, Pearson Product-Moment Correlation Coefficient, Spearman's rank correlation coefficient, Z-Score or standard score, Spearman's Footrule distance, Kendall tau rank coefficient, Jaccard similarity coefficient, Cayley's distance, hamming distance etc, since they cannot capture the similarity between genes with arbitrary time-delay and time-gap behavior, a novel algorithm, which enables time-delay alignment and time-gap alignment is proposed and integrated with some of those existing approaches which are local comparisons to fit into the underlying biological context. Time-delay behavior occurs when a gene's expression triggers a delayed expression in its co-regulated or anti-co-regulated peers. In addition, arbitrary time lag also might appear due to experiment error or measurement error. If any gene data has one or both of those condition, the similarity measurement using traditional methods will either under-estimate the similarity or completely miss such relationship. To align the gene data, an alignment algorithm that can be used to align time-delay as well as removing time-gap was developed. Because both Normal Euclidean Distance and Pearson Product-Moment Correlation Coefficient are local comparisons, the algorithm was able to integrate within those two approaches to accommodate the time-delay and time-gap behavior. All of the implementations are done through parallel programming of Message Passing Interface in C by splitting the work load dynamically from a master server to many slave servers in order to speed up the computation process. Synthetic and real microarray data are used to demonstrate the superior of our proposed method. The experimental results show that Normal Euclidean Distance and Pearson Product-Moment Correlation Coefficient with our alignment algorithm perform better in terms of capturing the similarity of more co-regulated or anti-regulated gene pairs. Some improvements such as isolation of experimental conditions, weighted averages and statistical analysis for threshold setting are proposed. Because such time-delay behavior in gene expression pattern is not unusual and usually play important roles in the cell system, the new approach will help scientists to discover important knowledge that otherwise will not be revealed. This approach is sensitive to capturing a wide spectrum of expression patterns, which tends to be ignored by traditional methods. Global comparison algorithms usually have a pre-step that normalize the entire dataset to achieve better result, thus the implemented time-delay and time-gap alignment algorithm will not be effective on the normalized data set. In order to cope with the intensive computing needs of large-scale microarray data, parallel code under message passing interface in C is developed with dynamic work load balancing strategy and executed at a Linux cluster.
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A study of procedures to examine correlation pattern hypotheses under conditions of multivariate normality and nonnormalityFouladi, Rachel Tanya 11 1900 (has links)
A wide array of procedures have been proposed for testing correlation pattern. Many, but
not all, of the statistical techniques available for testing correlation pattern are derived under the
distributional condition of multivariate normality which does not always hold in the behavioral,
educational and social sciences. Though a number of studies have explored the performance of
structure analysis techniques under conditions of multivariate nonnormality, very little is known
about the actual performance of many correlation structure analysis techniques under conditions
of multivariate nonnormality. In addition, very little is known about the actual concurrent
performance of tests of multivariate normality.
The present investigation ascertains how tests of correlation pattern hypotheses and
indicators of multivariate normality perform when data are from multivariate normal or nonnormal
parent populations. This paper reviews and examines, using a Monte Carlo simulation study, the
concurrent performance of different approaches to testing (1) correlation pattern hypotheses,
including, (i) normal theory (NT) and asymptotically distribution free (ADF) covariance structure
analysis techniques, (ii) NT and ADF correlation structure analysis techniques, (iii) correlation
pattern specific techniques; (2) the distributional assumption of multivariate normality using
statistics based on Mardia's measures of multivariate skewness and kurtosis. This paper also
examines the performance characteristics of test procedures based on joint consideration of tests
of multivariate normality and structure analysis techniques. Performance of the covariance and
correlation structure analysis techniques, tests of multivariate normality, and joint test procedures
was assessed across different types of correlation pattern models, numbers of variables, levels of
skew and kurtosis, sample sizes, and nominal alpha levels, on the primary Neyman-Pearson
criterion for an optimal test, according to which an optimal procedure (1) controls
experimentwise Type I error rate at or below the nominal level, (2) maximizes power. / Arts, Faculty of / Psychology, Department of / Graduate
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Correlation of dynamic probing light (DPL) and standard penetration test (SPT) for sandy soil of alluvial originPerez, Waldo Flores, Cerdena, Jorge Chavez, Ramirez, Gary Duran, Montoya, Maggie Martinelli 30 September 2020 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / In geotechnical studies, the dynamic probing light (DPL) turns out to be an alternative method to the Standard Penetration test (SPT) for the determination of soil parameters. The requirement of various regulations for correlating both tests in the same field and not establishing a methodology to carry it out, limits the practical scope of dynamic probing light. Thus, this research presents a correlation methodology between the dynamic probing light (DPL) and the Standard Penetration test (SPT) specifically for sandy soils (SP and SP-SM) located in an area of Chilca, located in Cañete. - Lima Peru. For the analysis, more than 400 data pairs were used, obtaining two linear correlations between the count blow of Standard Penetration-NSPT test and the dynamic probing light method-N10, which presented an adjustment correlation between 84% and 87 %.
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Correlation Studies in WheatReed, Joseph 01 May 1926 (has links)
Considerable work has been done by plant breeders and investigators in the study of individual plant characters, but only a few have attempted to work out correlations between characters in crop plants. One reason for this seems to be, that many investigators have felt that correlation studies were of very little practical value. This attitude was due perhaps to the interpretation given correlation data, especially the nature of the casual agency or agencies to which the correlation was attributed. Most of our plant breeders however, have been too busy working on experiments with single characters and have given little or no attention to correlation work. The few who have done work in correlations have usually found little or no correlation between the characters studied. The chief reason for lack of investigations in the field of correlations possibly lies in the fact that investigations in this field require very intricate and complex study. A number of characters must be studied and tabulated separately for each plant, the coefficient of correlation determined by means of a long mathematical process, and finally before the work is of any value, causal agencies must be considered and classified, and the data interpreted correctly. This makes the work slow and tedious.
It is quite natural then, in their rush to give to the world something new in plant breeding, that most of our investigators worked on individual characters. It is only recently that we have had men who have gone exhaustively into the field of correlations.
Before proceeding further, an explanation of correlations and what they indicate may be of value. Correlations as it relates to plant breeding is the association or relation that exists between plant characters due to a common casual agency or influence.
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Equalities and inequalities for canonical correlation coefficients, with emphasis on the two-way layout of experimental designLatour, Dominique January 1987 (has links)
No description available.
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Attitudes Towards Bisexuality and CorrelatesHutsell, David W., Chandler, Sheri L., Lund, Brittany K., Williams, Stacey L. 22 June 2012 (has links)
Attributions that point to sexual orientation being involuntary tend to be associated with more favorable attitudes toward homosexuals (Herek & Capitanio, 1995). Aside from attributions, those with more contact with sexual minorities are likely to have accepting attitudes about bisexuality (Mayfield & Carruba, 1996). Yet, the quality of the contact matters; research indicates that those with poorer qualitative contact have less positive attitudes toward homosexuals (Hodson, Harry, & Mitchell, 2009). Also, those with high religious beliefs are susceptible to beliefs of homosexuality as a choice and have more negative views (Kendra, Christopher, Franzen, & Keyes, 2006; Herek, 2002). While attitudes about homosexuality and bisexuality have been shown to be related, bisexuality is distinct from homosexuality and deserves separate focus (Mohr & Rochlen, 1999). The current study expands past research by examining a variety of factors related to attitudes toward bisexuality, such as perceiving sexual orientation as a choice, religiosity, and amount and quality of contact. Our first hypothesis is that both the perception of sexual orientation as a choice and higher levels of religiosity will relate to more negative attitudes toward bisexuals. Next, both the quantity and quality of contact with sexual minorities will predict attitudes such that less contact and less quality contact will be related to more negative attitudes toward bisexuals. We collected data from 1725 (67.2% female) individuals through participation in an online survey. Results indicate negative attitudes towards bisexuality are significantly related to the perception of sexual orientation as a choice (r = .499, p < .01) higher levels of religiosity (r = .515, p < .01) and lower levels of contact with sexual minorities (r = -.547; p < .01) and quality of contact (r = -.617; p< .01). These findings and comparisons of these relations by self-identified sexual orientation will be presented.
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On multiple correlation and its generalizationsSampson, George Theodore. January 1983 (has links)
No description available.
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Almost Sure Confidence Intervals for the Correlation CoefficientFridline, Mark M. January 2010 (has links)
No description available.
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The effect of autocorrelated errors on various least square estimators /Hong, Dun-Mow,1938- January 1971 (has links)
No description available.
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