Contrast Analysis on Single Factorial Studies and Solution with SPSS

Year 2019, Volume: 2 Issue: 1, 1 - 6, 01.01.2019

Demet Çanga , Aysel Yenipınar , Ömer Faruk Karaokur Ayşe Betül Önem , Ercan Efe

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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