Hi every one. I want to analyze my data. The y (density) is very skewed to the right. this is my tentative fit<-density~factor(Site)+factor(Species)+ depth. which model to apply between glm and lm, for sure I can not use lm( This is non linear data) -- View this message in context: http://r.789695.n4.nabble.com/regression-fit-tp4108686p4108686.html Sent from the R help mailing list archive at Nabble.com.
regression fit
2 messages · magushi, David Winsemius
On Nov 25, 2011, at 2:56 PM, magushi wrote:
Hi every one. I want to analyze my data. The y (density) is very skewed to the right. this is my tentative fit<-density~factor(Site)+factor(Species)+ depth. which model to apply between glm and lm, for sure I can not use lm( This is non linear data)
Until you have looked more carefully at your tentative fit you are jumping to unsupported assumptions. It is a common misconception that a skewed distribution of the dependent variable represents a problem for linear methods. It may be true but you will not know until you look at the distribution of the residuals of a linear fit. So far we see not evidence that you have done so. If you showed us plots of density ~ depth within categories of Site and Species then there might be a basis for discussion of alternative links or transformations. This wouldn't be homework by any chance, would it?
-- View this message in context: http://r.789695.n4.nabble.com/regression-fit-tp4108686p4108686.html Sent from the R help mailing list archive at Nabble.com.
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