Message-
> From: [EMAIL PROTECTED]
> [mailto:[EMAIL PROTECTED] On Behalf Of
> michael watson (IAH-C)
> Sent: Wednesday, April 06, 2005 7:18 AM
> To: John Fox
> Cc: r-help
> Subject: RE: [R] Help with three-way anova
>
> Hi John
>
> Thanks for your help, that was a ve
anks
Mick
-Original Message-
From: John Fox [mailto:[EMAIL PROTECTED]
Sent: 06 April 2005 12:52
To: michael watson (IAH-C)
Cc: 'r-help'; [EMAIL PROTECTED]
Subject: RE: [R] Help with three-way anova
Dear Mick,
For a three-way ANOVA, the difference between aov() and lm() is mostly
in th
chael watson (IAH-C)
> Sent: Wednesday, April 06, 2005 4:31 AM
> To: [EMAIL PROTECTED]
> Cc: r-help
> Subject: RE: [R] Help with three-way anova
>
> OK, now I am lost.
>
> I went from using aov(), which I fully understand, to lm()
> which I probably don't. I di
rying to
figure out what contrasts matrix I need to use...
Many thanks for your help
Mick
-Original Message-
From: Federico Calboli [mailto:[EMAIL PROTECTED]
Sent: 06 April 2005 10:15
To: michael watson (IAH-C)
Cc: r-help
Subject: RE: [R] Help with three-way anova
On Wed, 2005-04-06
On Wed, 2005-04-06 at 09:11 +0100, michael watson (IAH-C) wrote:
> OK, so I tried using lm() instead of aov() and they give similar
> results:
>
> My.aov <- aov(IL.4 ~ Infected + Vaccinated + Lesions, data)
> My.lm <- lm(IL.4 ~ Infected + Vaccinated + Lesions, data)
Incidentally, if you want
ferent to
zero? How do I interpret that?
Many thanks
Mick
-Original Message-
From: Federico Calboli [mailto:[EMAIL PROTECTED]
Sent: 05 April 2005 16:33
To: michael watson (IAH-C)
Cc: r-help
Subject: Re: [R] Help with three-way anova
On Tue, 2005-04-05 at 15:51 +0100, michael watson (IAH-C
Dear Michael,
For unbalanced data, you might want to take a look at the Anova()
function in the car package.
As well, it probably makes sense to read something about how linear
models are expressed in R. ?lm and ?formula both have some information
about model formulas; the Introduction to R manua
On Tue, 2005-04-05 at 15:51 +0100, michael watson (IAH-C) wrote:
> So, what I want to know is:
>
> 1) Given my unbalanced experimental design, is it valid to use aov?
I'd say no. Use lm() instead, save your analysis in an object and then
possibly use drop1() to check the analysis
> 2) Have I us
