I am running an nl procedure that searches for 13 parameters. When I
run the program, I obtain standard errors of 0 for many of the
parameters. The variance of these parameters is zero, according the
variance-covariance matrix. If I change the function tolerance via
eps(.), the number of parameters with no standard error changes. Could
anyone clue me in as to what might be going on?
Other questions I have are:
Is there a way to recover the gradient from the nl command? Also, is
there a way to change the optimization algorithm?
Thank you very much for any advice,
Amit Khandelwal
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