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PubMed · 10987205

Transformation in the PC-aided biochemical data analysis.

M Meloun·M Hill·J Militký·K Kupka
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Abstract

Data transformations enable expression of original data in a new scale, more suitable for data analysis. In computer-aided interactive analysis of biochemical and clinical data an exploratory data analysis often finds that the sample distribution is systematically skewed or does not accept a sample homogeneity. Under such circumstances the original data should be transformed. The power transformation and the Box-Cox transformation improve sample symmetry and also stabilize variance. Both the Hines-Hines selection graph and the plot of logarithm of a maximum likelihood function allow selection of an optimum transformation parameter. The proposed procedure of data transformation in univariate data analysis is illustrated on a determination of 17-hydroxypregnenolone in umbilical blood of a population of newborns. Lower levels of free 5-ene steroids in umbilical blood and elevated levels of 5-ene steroid sulfates indicate a congenital sex-specific placental sulfatase insufficiency. After examination of statistical assumptions by diagnostic plots of an exploratory data analysis the best estimate of a mean value of 17-hydroxypregnenolone is derived.

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17-alpha-HydroxypregnenoloneBiochemical PhenomenaBiochemistryFetal BloodHumansInfant, NewbornMicrocomputersStatistics as TopicJournal ArticleResearch Support, Non-U.S. Gov't

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M Meloun, M Hill, J Militký, K Kupka. 2000. Transformation in the PC-aided biochemical data analysis.. https://doi.org/10.1515/cclm.2000.081

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17-alpha-Hydroxypregnenolone↗
PubMed2006

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PubMed2006

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