Dear S Ellison, If I understand correctly what you said, a plot of residuals against an X is not an added-variable plot. An added variable plot is constructed by regressing Y on all the Xs but the focal X, and regressing the focal X on all the other Xs; then the residuals from the first regression are plotted against the residuals from the second.
As Denis Cook has shown, AV plots, while very useful for visualizing influence and leverage on the coefficients (and for other purposes) are not good nonlinearity diagnostics; for that purpose component+residual (partial residual) plots and their variations are better. Both added-variable and component+residual plots are available in the car package; see ?avPlots, ?crPlots. Best, John ------------------------------------------------ John Fox Sen. William McMaster Prof. of Social Statistics Department of Sociology McMaster University Hamilton, Ontario, Canada http://socserv.mcmaster.ca/jfox/ On Wed, 14 Sep 2011 16:07:24 +0100 S Ellison <s.elli...@lgcgroup.com> wrote: > > > > -----Original Message----- > > From: r-help-boun...@r-project.org > > [mailto:r-help-boun...@r-project.org] On Behalf Of Patrick Breheny > > > > The latter type of plot is called a "partial regression plot" > > or "added variable plot". They are discussed in any > > regression textbook, as well as wikipedia and probably dozens > > of other web sites. > > They are also available in the car package. > > S Ellison******************************************************************* > This email and any attachments are confidential. Any use...{{dropped:8}} > > ______________________________________________ > 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.
