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
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