That's because you have not specified the random effect. I think you want
lme(Error ~ Sequence + Temperature + Tumour, random = ~1|ID, data = YourDataset)
HTH,
Thierry
----------------------------------------------------------------------------
ir. Thierry Onkelinx
Instituut voor natuur- en bosonderzoek / Research Institute for Nature and
Forest
Cel biometrie, methodologie en kwaliteitszorg / Section biometrics, methodology
and quality assurance
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-----Oorspronkelijk bericht-----
Van: r-help-bounces op r-project.org [mailto:r-help-bounces op r-project.org]
Namens Dani Valverde
Verzonden: zaterdag 24 mei 2008 11:01
Aan: R Help
Onderwerp: [R] Problems with lme
Hello,
I want to perform an lme on a database with this structure:
ID Sequence Temperature Tumour Error
1 5 0 1 8.721872e-08
1 5 0 2 8.695348e-08
1 5 0 3 2.019604e-13
1 5 37 1 2.746476e-01
1 5 37 2 1.580415e-02
1 5 37 3 1.586857e-01
1 2 0 1 8.721872e-08
1 2 0 2 8.695348e-08
1 2 0 3 2.019604e-13
1 2 37 1 2.746476e-01
I try to perform an lme with the lme() function of the lme package
(first I attach the data frame with attach()). This is the code:
lme(Error ~ ID + Sequence + Temperature + Tumour)
If I use this code, I get the following error:
Error in getGroups.data.frame(dataMix, groups) :
Invalid formula for groups
Can anyone help me?
Best,
Dani
--
Daniel Valverde Saub?
Grup de Biologia Molecular de Llevats
Facultat de Veterin?ria de la Universitat Aut?noma de Barcelona
Edifici V, Campus UAB
08193 Cerdanyola del Vall?s- SPAIN
Centro de Investigaci?n Biom?dica en Red
en Bioingenier?a, Biomateriales y
Nanomedicina (CIBER-BBN)
Grup d'Aplicacions Biom?diques de la RMN
Facultat de Bioci?ncies
Universitat Aut?noma de Barcelona
Edifici Cs, Campus UAB
08193 Cerdanyola del Vall?s- SPAIN
+34 93 5814126
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