Hi, A error message arose while I was trying to fit a ordinal model with lrm() I am using R 2.8 with Design package.
Here is a small set of mydata: RC RS Sex CovA CovB CovC CovD CovE 2 1 0 1 1 0 -0.005575280 2 2 1 0 1 0 1 -0.001959580 2 3 0 0 0 1 0 -0.004725880 2 0 0 0 1 0 0 -0.005504850 2 2 1 1 0 0 0 -0.003880170 1 2 1 0 0 1 0 -0.006074230 2 2 1 0 0 1 1 -0.003963920 2 2 1 0 0 1 0 0.000658230 2 2 1 0 1 0 1 -0.002033610 2 0 0 0 0 0 1 -0.007761770 2 0 0 0 0 1 1 -0.000951784 2 Note: In the complete data, there are NAs. But the error messages showed in both the complete and above sets. >attach(mydata) >lrm(RC~RS+Sex+CovA+CovB+CovC+CovD+CovE,data=mydata,na.action=na.pass) singular information matrix in lrm.fit (rank= 8 ). Offending variable(s): CovE Error in j:(j + params[i] - 1) : NA/NaN argument >detach(mydata) >lrm(mydata$RC~ mydata$RS+ mydata$Sex+ mydata$CovA+ mydata$CovB+ mydata$CovC+ >mydata$CovD+ mydata$CovE,data=mydata,na.action=na.pass) Error in if (!length(fname) || !any(fname == zname)) { : missing value where TRUE/FALSE needed I have debugged for a while, but no success. Does anyone know what happens? Thanks, Mike ______________________________________________ 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.