On Thu, 24 Jan 2008, Martin Eklund wrote: > Dear R users, > > I'm wondering about the singular.ok option in lm. If singular.ok is > set to TRUE does it mean that we allow the generalized inverse of > (X'X)^-1 (where X are the independent variables and ' denotes the > transpose)? Or is the singularity handled in some other way?
Pivoting is used: singular.ok=TRUE is the default in R. I don't think you can say *the* generalized inverse: there are many. In any case, R does not solve the normal equations let alone invert X'X to fit a regression. > ======================================== > Martin Eklund > PhD Student > Department of Pharmaceutical Biosciences > Uppsala University, Sweden > Ph: +46-18-4714281 > ======================================== -- Brian D. Ripley, [EMAIL PROTECTED] Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595 ______________________________________________ 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.
