On 3/5/2009 7:53 AM, Sueli Rodrigues wrote:>
> Hello. I have a file with 480 lines but each 6 lines corresponding just
> one sample. How can can work out the linear regression to each 6 lines?
> I use the model: model=lm(y~x)
mydf <- data.frame(X = rnorm(480), Y = rnorm(480))
mydf$SAMPLE <- rep(1:80, each=6)
by(mydf, mydf$SAMPLE, function(x){summary(lm(Y ~ X, data = x))})
OR
lapply(split(mydf, mydf$SAMPLE), function(x){summary(lm(Y ~ X, data = x))})
OR
library(nlme)
fm1 <- lmList(Y ~ X | SAMPLE, mydf)
summary(fm1)
> Sueli Rodrigues
>
> Agronomy Eng. - UNESP
> Master Degree - USP/ESALQ
> PPG-Soils and Plants Nutrition
> Phones(19)93442981
> (19)33719762
>
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