ABSTRACT
The analysis of variance technique may be applied to a great variety of complex experiments. In many experiments, we study the effects of two or more factors simultaneously. In such experiments, we can get some addi tional information if we use a group analysis technique. Every degree of freedom in a statistical problem can be used to provide information of some statistical interest. A procedure for subdivision of the sum of squares of treatments, each of which has one degree of freedom, is explained in this chapter._We compare onejreatment with the other. If there are two treatment means, 71 and 72, then 71 - 72 is a comparison or a contrast. If there are three treatments, a pairwise comparisonof twoTreatments can be made in three different ways, e.g., 71 - 72, 71 - 73, and 72 - 73. Ajso, we can get_a comparison average of the two means with the third one [(71 +T2)]/2-73 (where 71, and 72 aresimilar Jiut differ considerably from 73), [(71 + 73)]/2 - 72 and [(72 + 73)1/2 - 71. In these situations, we can make use of group comparison analysis; it is convenient to work with the totals of treat ments when the numbers of replications are equal in each treatment. We will define some of the terms that are commonly used.
