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Orthogonal contrasts and planned contrasts

Author Affiliations

  • 1St. Xavier’s College, Kolkata, India

Res. J. Mathematical & Statistical Sci., Volume 6, Issue (8), Pages 7-10, December,12 (2018)


In analysis of variance, the F-test fails to identify the cause behind the differential effect among the levels of the treatment under consideration. That cause can be easily pointed out through contrasts. Either the investigator plans the contrasts of interest prior to the study or the experimenter searches for something unexpected after the experiment is over, allowing the data itself to suggest additional interesting contrasts. Orthogonality of the contrasts is an important feature which facilitates the testing procedures.


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