R code:
dat.aov = aov(lm(weight~ factor(Time)+Diet+factor(Time):Diet,
data=ChickWeight))
summary(dat.aov)
Output:
summary(dat.aov)
                 Â
Df Sum Sq Mean Sq F value  Pr(>F) Â
factor(Time)Â Â Â Â Â Â 11 2067050 187914
157.808 < 2e-16 ***
Diet                 Â
3 129721Â Â 43240 36.313 < 2e-16 ***
factor(Time):Diet 33Â Â 86676Â Â Â
2627Â Â 2.206 0.000172 ***
Residuals        530
631110Â Â Â
1191Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â
---
Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
|
df |
SS |
MS |
F |
Pr(>F) |
factor(Time) |
11 |
2067050 |
187914 |
157.808 |
2e-16 |
Diet |
3 |
129721 |
43240 |
36.313 |
2e-16 |
factor(Time):Diet |
33 |
86676 |
2627 |
2.206 |
0.00017 |
Residuals |
530 |
631110 |
1191 |
3. F = 2.206
4. Fα = F0.05,33,530=1.4585
5. Conclusion:
Reject H0
(since F>Fα)
Interpretation:
There is sufficient evidence to support that the interaction
between Time and Diet is significant.