You should not need to write them yourself. Look at the contr.poly function
along with the C function (Note uppercase C) or the contrasts function.
On Monday, July 23, 2012, Manzoni, GianMauro wrote:
> Dear all,
> I am quite new to R and I am having trouble writing the polynomial
> contrasts for an ordinal factor in MANOVA.
> # I have a model such as this
> fit<-manova(cbind(Y1,Y2,Y3)~Groups,data=Events) # where groups is an
> ordinal factor with 4 levels
> # how to set polynomial contrasts for the "Groups" factor ?
>
> Thank you very much in advance for any help!
>
> Best regards,
> Mauro
>
> --
> Dr. Gian Mauro Manzoni
> PhD, PsyD
> Psychology Research Laboratory
> San Giuseppe Hospital
> Istituto Auxologico Italiano
> Verbania - Italy
> e-mail: gm.manzoni@auxologico.it <javascript:;>
> cell. phone +39 338 4451207
> Tel. +39 0323 514278
>
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>
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--
Gregory (Greg) L. Snow Ph.D.
538280@gmail.com
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