[R] [FORGED] Re: Dunnett Test in 'multicomp' package

[Gerrit Eichner]

Hello, everyone,

aside from Rolf's hint (and Richard's warning!) you could also consider 
relevel():

viagraData$dose <- relevel( viagraData$dose, ref = "placebo")

  Hth  --  Gerrit

On Fri, 5 Jun 2015, Rolf Turner wrote:

> On 05/06/15 11:08, Jim Lemon wrote:
>> Hi James,
>> You can change the order of levels like this:
>> 
>> levels(viagraData$dose)<-c("placebo","low dose","high dose")
>
> <SNIP>
>
> As Richard Heiberger has pointed out, this is wrong.
>
> What *does* work is:
>
> viagraData$dose)<-factor(viagraData$dose,
>                        levels=c("placebo","low dose","high dose")
>
> This is a trap into which many a Young Player (including my very good self) 
> has fallen.
>
> cheers,
>
> Rolf Turner
>
>
>
> -- 
> Technical Editor ANZJS
> Department of Statistics
> University of Auckland
> Phone: +64-9-373-7599 ext. 88276
>
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