The application of orthogonal contrasts to determine homogeneous groups
The paper presents a modified approach to analysis of data obtained from experiments carried out according to classical factorial designs. Four examples were discussed in order to present details of proposed method. Modification of the analysis of variance presented here enables more effective use of information on how studied factors affect the means of dependent variable. The specificity of this approach is based on alternative multiple comparison procedure incorporating orthogonal contrasts to determine homogeneous groups.
experiment; data analysis; linear model; ANOVA; multiple comparisons; orthogonal contrasts
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