ABSTRACT
Suppose you have N homogeneous experimental units and you randomly divide them into t groups of n
units each where
n
=
N
. Each of the t treatments of a one-way treatment structure is randomly assigned to one group of experimental units, providing a one-way treatment structure in a completely randomized design structure. It is assumed that the experimental units are subjected to their assigned treatments independently of each other. Let y
(dependent variable) denote the j
observation from the i
treatment and x
denote the covariate (independent variable) corresponding to the (i,j)
experimental unit. As in Chapter 1, the values of the covariate are not to be influenced by the levels of the treatment. The best case is where the values of the covariate are determined before the treatments are assigned. In any case, it is a good strategy to use the analysis of variance to check to see if there are differences among the treatment covariate means (see Chapter 18).
