I run R to calculate ability values of about 20k students who took a test. I face the following issues.
- I am unable to get output with entries for all the students. Getting output using write.table option works but I found about 100 entries missing. - How to get output of item parameters upon fitting 3PL model in an external text file? - Is it possible to feed in response matrix along with unique student ids and get the output along with student ids? If yes, how? - At times a get a warning message "Hessian matrix is convergence is not positive definitite; solution is unstable." What could be the reason for this? - Can I run R script from PHP? Regards, Maulik Shah [[alternative HTML version deleted]] ______________________________________________ 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.