On 8/8/05, Krishna <[EMAIL PROTECTED]> wrote: > Hi Everyone > > May I request for a small help while performing the regression analysis. > > I would like to know is there any possibility of conducting the > regression for different data subsets (in the same data file), > classified on the basis of "grouping variable". The alternative for > this is running the regression for n number of times which you all > know is quite cumbersome.
This defines a model which has a separate intercept and slope for each value of the grouping variable g: > # sample data > x <- 1:12 > g <- gl(4,3) > g [1] 1 1 1 2 2 2 3 3 3 4 4 4 Levels: 1 2 3 4 > set.seed(1) > y <- rnorm(12) > # now define the model and run the regression > lm(y ~ g/x - 1) Call: lm(formula = y ~ g/x - 1) Coefficients: g1 g2 g3 g4 g1:x g2:x g3:x g4:x -0.21697 6.40748 0.24710 -3.29170 -0.10459 -1.20787 0.04418 0.34762 ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html