Message-ID: <FF722405-D2AB-48EF-95B6-E34BB42CCF9B@imperial.ac.uk>
Date: 2008-05-12T09:50:03Z
From: Federico Calboli
Subject: lme nesting/interaction advice
In-Reply-To: <20080512000558.GA20606@ms.unimelb.edu.au>
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
>>>> effect,
>>>> 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
>>>> Stats
>>>> course here[1].
>>>
>>> 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,
> Rolf?
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.
Bog standard models are *likely* to be used over and over again
because they are *bog standard*, and they became such by being used
*lots*.
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.
Regards,
Federico
--
Federico C. F. Calboli
Department of Epidemiology and Public Health
Imperial College, St. Mary's Campus
Norfolk Place, London W2 1PG
Tel +44 (0)20 75941602 Fax +44 (0)20 75943193
f.calboli [.a.t] imperial.ac.uk
f.calboli [.a.t] gmail.com