[R-sig-ME] [R] lme nesting/interaction advice
A.Robinson at ms.unimelb.edu.au
Mon May 12 12:16:26 CEST 2008
On Mon, May 12, 2008 at 10:50:03AM +0100, Federico Calboli wrote:
> On 12 May 2008, at 01:05, Andrew Robinson wrote:
> >On Mon, May 12, 2008 at 10:34:40AM +1200, Rolf Turner wrote:
> >>On 12/05/2008, at 9:45 AM, Andrew Robinson wrote:
> >>>On Sun, May 11, 2008 at 07:52:50PM +0100, Federico Calboli wrote:
> >>>>The main point of my question is, having a 3 way anova (or
> >>>>ancova, if
> >>>>you prefer), with *no* nesting, 2 fixed effects and 1 random
> >>>>why is it so boneheaded difficult to specify a bog standard fully
> >>>>crossed model? I'm not talking about some rarified esoteric model
> >>>>here, we're talking about stuff tought in a first year Biology
> >>>>course here.
> >>>That may be so, but I've never needed to use one.
> >> So what? This is still a standard, common, garden-variety
> >> model that you will encounter in exercises in many (if not
> >> all!) textbooks on experimental design and anova.
> >To reply in similar vein, so what? Why should R-core or the R
> >community feel it necessary to reproduce every textbook example? How
> >many times have *you* used such a model in real statistical work,
> There is a very important reason why R (or any other stats package)
> should *easily* face the challenge of bog standard models: because it
> is a *tool* for an end (i.e. the analysis of data to figure out what
> the heck they tell us) rather than a end in itself.
But a tool that mostly (entirely?) appears in textbooks.
> Bog standard models are *likely* to be used over and over again
> because they are *bog standard*, and they became such by being used
Well. I have documentation relevant to nlme that goes back about 10
years. I don't know when it was first added to S-plus, but I assume
that it was about then. Now, do you think that if the thing that you
want to do was really bog standard, that noone would have raised a
fuss or solved it within 10 years?
> If someone with a relatively easy model cannot use R for his job s/he
> will use something else, and the R community will *not* increase in
> numbers. Since R is a *community driven project*, you do the math on
> what that would mean in the long run.
Fewer pestering questions? ;)
Department of Mathematics and Statistics Tel: +61-3-8344-6410
University of Melbourne, VIC 3010 Australia Fax: +61-3-8344-4599
More information about the R-sig-mixed-models