The application of orthogonal contrasts to determine homogeneous groups


Abstract

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.


Keywords

experiment; data analysis; linear model; ANOVA; multiple comparisons; orthogonal contrasts

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Published : 2021-12-02


Laudański, Z., Mańkowski, D., Sieczko, L., & Janaszek-Mańkowska, M. (2021). The application of orthogonal contrasts to determine homogeneous groups. Plant Breeding and Seed Science, 82, 31-44. https://doi.org/10.37317/pbss-2021-0003

Zbigniew Laudański 
Plant Breeding and Acclimatization Institute — National Research Institute in Radzików, Poland  Poland
Dariusz Mańkowski  d.mankowski@ihar.edu.pl
Plant Breeding and Acclimatization Institute - National Research Institute  Poland
https://orcid.org/0000-0002-7499-8016
Leszek Sieczko 
Institute of Agriculture — Warsaw University of Life Sciences, Poland  Poland
Monika Janaszek-Mańkowska 
Institute of Mechanical Engineering — Warsaw University of Life Sciences, Poland  Poland




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