[R] ANOVA error

Peter Alspach PAlspach at hortresearch.co.nz
Thu Jun 19 22:28:51 CEST 2008


Dani

> I have a dataframe named myMatrix with the structure

If it really is a dataframe, why is it called myMatrix :-)  I guess you actually have a factor matrix.  From the message below, Cr would appear to be a factor.

There are some fundamental distinctions in R (such as between a matrix and a dataframe, or between factor and numeric) which can seem 'subtle' as first.  It is worth investing a bit of effort into understanding these. [My apologies if this is stating something which is obvious to you.]

HTH ....

Peter Alspach

> Treatment    Time    Cr    mIb ...
> 
> Being the treatment and time the predictors and Cr, mIb and 
> so on the response variables. When I call
> 
> Cr.aov <- aov(Cr~Treatment, data=myMatrix)
> 
> I got this error:
> 
> Error in storage.mode(y) <- "double" :
>   invalid to change the storage mode of a factor In addition: 
> Warning message:
> In model.response(mf, "numeric") :
>   using type="numeric" with a factor response will be ignored
> 
> Can anyone help me? I take the chance to ask another 
> question. I would like to perform an ANOVA on different 
> variables. Is the call aov(Cr+mIb+...~Treatment, 
> data=myMatrix) o correct way of doing it? What I would like 
> to have is a p value for the variance for each response variable.
> Best,
> 
> Dani
> 
> --
> Daniel Valverde Saubí
> 
> Grup de Biologia Molecular de Llevats
> Facultat de Veterinària de la Universitat Autònoma de 
> Barcelona Edifici V, Campus UAB
> 08193 Cerdanyola del Vallès- SPAIN
> 
> Centro de Investigación Biomédica en Red en Bioingeniería, 
> Biomateriales y Nanomedicina (CIBER-BBN)
> 
> Grup d'Aplicacions Biomèdiques de la RMN Facultat de 
> Biociències Universitat Autònoma de Barcelona Edifici Cs, Campus UAB
> 08193 Cerdanyola del Vallès- SPAIN
> +34 93 5814126
> 
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide 
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
> 

The contents of this e-mail are privileged and/or confidential to the named
 recipient and are not to be used by any other person and/or organisation.
 If you have received this e-mail in error, please notify the sender and delete
 all material pertaining to this e-mail.



More information about the R-help mailing list