A second issue that puzzles me is that you mentioned that following the 5 November 2003 update, the -nrtolerance(1e-5)- became the default
convergence criterion. If that is the case, then how is possible that when I specify version 8.0 within stata and run the command, I am still faced with this problem of non-convergence? Is it the case that once I have updated from Stata 8.0 to 8.2, my software automatically overrides the previous nrtolerance to the new one, and this becomes the default no matter what version I specify when running the frontier command with maximise options? Or am I wrong in thinking that nrtolerance is comparable with any other command which are outdated in the new version and can be run only in an older version and, therefore, should not have produced this problem of non-convergence in the first instance, when I tried to run the command under version 8.0?
Finally, I will attempt you suggestion of multiplicative rescaling of the variables. I did try changing the starting values before I posted this query, but that did not work either.
Many thanks for your help.
Dev
This message has been scanned but we cannot guarantee that it and any
attachments are free from viruses or other damaging content: you are
advised to perform your own checks. Email communications with the
University of Nottingham may be monitored as permitted by UK legislation.
*
* For searches and help try:
* http://www.stata.com/support/faqs/res/findit.html
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
