
6 Fit Y by X Platform Introduction 135
6 Fit Y by X: Comparing Two Variables
Analysis of Variance (ANOVA)
Is knowledge of the wash method useful in predicting starch content of the denim? The statistical test
to answer this question is called a one-way
ANOVA, and is produced in the same way as the t-test above.
Select
Means/Anova from the drop-down menu next to Oneway Analysis.
Note that the command reads
Means/Anova/t test when the categorical variable has only two levels.
In all other cases (like this one), the t test is not appropriate, so is not available on the menu.
An
ANOVA table appears beneath the plots, and means diamonds appear on the ...