[R] subset factor?

[Silvano]

Hi,

I used subset command, like this:

grupoP = subset(dados, grupos=='P',  select=c(mortos, vivos, 
doses, percevejos, p))

and the variables in select option are numeric.

I tried fit a model with command:

ajuste.logit = glm(cbind(mortos,percevejos)~log10(doses), 
family=binomial(logit), data=grupoP)

and the output is:

> ajuste.logit = glm(cbind(mortos,percevejos)~log10(doses), 
> family=binomial(logit), data=grupoP)
Erro em Math.factor(doses) : log10 not meaningful for 
factors

what is wrong with my commands? Why doses aren't numeric?

Thanks,

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Silvano Cesar da Costa
Departamento de Estatística
Universidade Estadual de Londrina
Fone: 3371-4346