[R] Difference in ANOVA results - R vs. JMP/Minitab

[Nirmal Govind]

Thank you very much John and Sundar for your quick responses.

>  From your description, it's not possible to tell what you did or 
> exactly what happened -- either in R or in Minitab (and JMP).

John: in R, I fit the model using lm exactly as you did.. however, for 
the ANOVA table, I used summary(lm) and also tried aov(lm) but not 
anova(lm) ... and it looks like therein lies the problem.. the output of 
these differ.

What's the difference between aov, summary and anova? And when should 
one use one as opposed to the other? It's hard to tell from the help for 
these functions...

Thanks,
nirmal