[R-sig-ME] [R] lme nesting/interaction advice
David.Duffy at qimr.edu.au
Mon May 12 03:22:10 CEST 2008
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.
> y ~ effect1 * effect2 * effect3
> with effect3 being random (all all the jazz that comes from this
> fact). I fully apprecciate that the only reasonable F-tests would be
> for effect1, effect2 and effect1:effect2, but there is no way I can
> use lme to specify such simple thing without getting the *wrong*
> denDF. I need light on this topic and I'd say it's a general enough
You _might_ be able to use the kinship package (lmekin, which in turn uses
lme) for this. I'm just not sure about the "random regression"
(fixed:random) interaction terms.
| David Duffy (MBBS PhD) ,-_|\
| email: davidD at qimr.edu.au ph: INT+61+7+3362-0217 fax: -0101 / *
| Epidemiology Unit, Queensland Institute of Medical Research \_,-._/
| 300 Herston Rd, Brisbane, Queensland 4029, Australia GPG 4D0B994A v
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