Contrast Analysis on Single Factorial Studies and Solution with SPSS

Abstract

Contrast analysis is a method for comparing sets of means using specific coefficients for weighting the means. In this study, contrast analysis as a planned comparison method and its use in one-factor trial designs are examined. For this purpose, a hypothetical data set is used to analyze the data related to the amount of dry matter determined by three different methods. The steps of the contrast analysis are explained using the SPSS.18 package program. In conclusion, contrast analysis results showed that a great part of the difference between the methods is due to the difference between method 3 and the others (p <0.01) according to F test detailed with 1 degree of freedom.

Keywords

• ANOVA,Contrast,Mean comparison,Trial plans

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