[R] Understanding lm-based analysis of fractional factorial experiments

[Kjetil Kjernsmo]

On 03/06/2013 04:18 PM, Peter Claussen wrote:
> I'll ignore the rest of your question, in the hope that this will answer them sufficiently.

OK!

> You probably want a simple linear model, specified in R using "+" instead of "*".
>
>> >leaf.lm <- lm(yavg ~ B + C + D + E + Q, data=leaf)
>> >leaf.lm
> Call:
> lm(formula = yavg ~ B + C + D + E + Q, data = leaf)
>
> Coefficients:
> (Intercept)           B+           C+           D+           E+           Q+
>      7.50084      0.22125      0.17625      0.02875      0.10375     -0.25960
>
> Does this give you the numbers you expect?

Well, it partly gives the numbers I expect, but I want the interactions 
as well, so it is only a partial answer.

Best,

Kjetil