To get at the effect of d in the model y~ a+b+c+d you need to look at the regression of the residuals of y ~ a+b+c on the residuals of d ~ a+b+c, that should give you the same results/significance as d in the full model. If you only regress the residuals against d, then that does not adjust for the relationship between d and a, b, and c as the full model does.
Hope this helps, -- Gregory (Greg) L. Snow Ph.D. Statistical Data Center Intermountain Healthcare [EMAIL PROTECTED] 801.408.8111 > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] > project.org] On Behalf Of Manuel Ramon > Sent: Tuesday, November 18, 2008 2:23 AM > To: r-help@r-project.org > Subject: [R] Re siduals from a linear model > > > I'm working with a linear model with four factors as explicatory > variables, > being all of them significally (e.g. y ~ a + b + c + d). I thought that > the > residuals of a linear model keep the variance not explained by the > model, so > if I use my model with just three factors (y ~ a + b + c) and keep the > residuals is expected that in a new model with the residuals as > dependent > variable and the four factor as independent (residuals ~ d) that factor > (d) > will be significally. Is that truth or not? > > > > ----- > Manuel Ramón Fernández > Group of Reproductive Biology (GBR) > University of Castilla-La Mancha (Spain) > [EMAIL PROTECTED] > -- > View this message in context: http://www.nabble.com/Residuals-from-a- > linear-model-tp20556033p20556033.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting- > guide.html > and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
