Hi everyone, I'm running a factor analysis on a correlation matrix with 32 rows and columns. I get the following error when I issue the command sequence mich.fac1 <- factanal(michcor, factor=1) Error in solve.default(cv) : system is computationally singular: reciprocal condition number = 3.24729e-18 I'd really appreciate an explanation for this error and a solution to the problem Thanks Steve [[alternative HTML version deleted]]
Steve Friedman wrote:> Hi everyone, > > > I'm running a factor analysis on a correlation matrix with 32 rows and > columns. > > I get the following error when I issue the command sequence > > mich.fac1 <- factanal(michcor, factor=1) > Error in solve.default(cv) : system is computationally singular: reciprocal > condition number = 3.24729e-18 >As the message tells us: Your correlation/covariance matrix is (almost) singular, hence the inverse cannot be computed. Do you have many zeros in there??? Or identical columns for some other reasons? Uwe Ligges> > I'd really appreciate an explanation for this error and a solution to the > problem > > Thanks > Steve > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at 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.
At 17:51 06/10/2007, Steve Friedman wrote:>Hi everyone, > > >I'm running a factor analysis on a correlation matrix with 32 rows and >columns. > >I get the following error when I issue the command sequence > >mich.fac1 <- factanal(michcor, factor=1) >Error in solve.default(cv) : system is computationally singular: reciprocal >condition number = 3.24729e-18 > > >I'd really appreciate an explanation for this error and a solution to the >problem?factanal reveals that factanal(x, factors, data = NULL, covmat = NULL, n.obs = NA, subset, na.action, start = NULL, scores = c("none", "regression", "Bartlett"), rotation = "varimax", control = NULL, ...) and x A formula or a numeric matrix or an object that can be coerced to a numeric matrix. I think you meant covmat = michcor>Thanks >Steve > > [[alternative HTML version deleted]]Michael Dewey http://www.aghmed.fsnet.co.uk