Page 227 - Intermediate Statistics for Dummies

18_045206 ch12.qxd 2/1/07 10:20 AM Page 206
206
Part III: Comparing Many Means with ANOVA
y
Figure 12-2:
y
Connecting
means of
populations
to the slope
of a line.
x
2
1
4
3
Indeed (the stat professor’s way of saying “and this is the really cool part. . .”),
if you look at the value of the t-statistic for testing the slope of the education
variable in Figure 12-1, you see that it’s 13.18 (look at the row marked
Education and the column marked T). Square that value, and you get 173.71.
The F-statistic in the ANOVA table of Figure 12-1 is equal to 173.75. The
F-statistic from ANOVA and the t-statistic from regression are equal to each
other in Figure 12-2, subject to a little round-off error done by Minitab on the
output. (Just like magic! I still get chills just thinking about it.)