On Fri, 20 Feb 2009, GAF wrote: > > Hi there, > I am trying to measure orthogonal/perpendicular distances from regression > lines (i.e. the shortest distance from a given point to my regression line). > As it sounds rather easy (basically just an orthogonal/perpendicular > residual) I hoped that there was some function in R that can do that. All > efforts so far remained unsuccessful, however. > Does anybody know?
You could do this with [1], but if you are hoping to learn something statistical by doing this you should probably reconsider, because the regression line residuals are minimized along the dependent variable axis, and if the coordinate system is rotated (that is, you look at deviation from the regression line to the points along a different direction) then the residuals on that regression line will no longer be minimized. [1] http://mathworld.wolfram.com/Point-LineDistance2-Dimensional.html --------------------------------------------------------------------------- Jeff Newmiller The ..... ..... Go Live... DCN:<jdnew...@dcn.davis.ca.us> Basics: ##.#. ##.#. Live Go... Live: OO#.. Dead: OO#.. Playing Research Engineer (Solar/Batteries O.O#. #.O#. with /Software/Embedded Controllers) .OO#. .OO#. rocks...2k ______________________________________________ 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.
