Statistics Meeting Book (February 20, 2019)

General assumptions (both metamers) • ‘Independence’: Sources of variation do not interact. The underlying model is additive and main effects only. • ‘Homogeneity’: Sources of variation are the same for each Institution, characterized by a common variance. • ‘Normality’: Sources of variation are governed by a univariate normal distribution, so only means and variances matter. C metamer • Useful for a fixed single concentration where observed concentrations vary well within one order of magnitude. • Results for different concentrations generally not comparable unless macro analyte in the 10% to 100% composition range. • Data subject to skew and kurtosis (failures of normal distribution assumption) copyright 2018 by Least Cost Formulations, Ltd., all rights reserved.

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copyright 2018 by Least Cost Formulations, Ltd., all rights reserved.