In a study consisting of four groups, each with ten subjects, the following results were obtained:
(a) Write the regression equation that will be obtained if effect coding is used. Assume that subjects in the fourth group are assigned -1'so
(b) What are the effects of the four treatments?
(c) What is the residual sum of squares?
(d) What is the regression sum of squares?
(e) What is R2?
(f) What is the overall F ratio?
(g) Do Schaffer tests for the following comparisons,
Using α = .05: (1) between
1
and
2;
(2) between the mean of
1
and
2, and
3;
(3) between the mean of
1.
2,
4, and
3.