I don't know exactly how the convergence criterion is calculated, but it is
usually based on a quadratic form that g'*inv(D)*g where g is the gradient
and D is the Hessian (or equivalent depending on algorithm). Basically the
sum of the (squared) elements of the gradient are being weighted by their
estimated precisions. I bet that is how it is computed. The non
convergence example is pretty bad. the norm (of the gradient?) is huge.
Lee
On Fri, Sep 2, 2016 at 11:15 AM, Mario Flórez Porras <
mario.florez.porras(a)gmail.com> wrote:
Beforehand, thank you very much for answer.
I know how to set the tolerance parameter. What I want to know if possible
is how gretl calculate whether my model mets the tolerance?
El 1/09/2016 a las 8:43 a. m., Sven Schreiber escribió:
>
> Am 25.08.2016 um 23:42 schrieb Mario Florez Porras:
>
>> Hello,dear Gretl Community.
>>
>> I'm doing a nonlinear estimation via the maximum likelihood method. I
>> want to do a batch processing of data but in some cases the estimation
>> don't satisfise tolerance (1,81899e-012), don't met the convergence
>> criterion. Does anyone knows how it is calculated whether or not the
>> model meets tolerance?
>>
>>
> Apparently nobody wants to answer in the holiday season....
>
> There is a settable option using the "set" command for the MLE tolerance.
> See the "set" documentation under the section "Numerical methods"
in the
> built-in command reference; as in:
>
> set bfgs_toler <some-value>
>
> You may have to also choose the optimizer for ML explicitly before the
> mle block, as in:
>
> set optimizer BFGS
>
> Some remarks to the masters of the documentation: First I don't see a
> "newton_toler" option and I don't immediately understand why this is
> absent. Also the way to adjust the tolerance setting might be mentioned in
> the MLE chapter of the guide, I didn't see it there (but may have missed
> it), I only saw a mention of choosing the optimizer.
>
> OK, but after all these technicalities, I'd say the default tolerance
> values are reasonable, and if you get a problem there you're better off
> transforming your data instead (normalizing etc.).
>
> good luck,
> sven
>
>
> _______________________________________________
> Gretl-users mailing list
> Gretl-users(a)lists.wfu.edu
>
http://lists.wfu.edu/mailman/listinfo/gretl-users
>
_______________________________________________
Gretl-users mailing list
Gretl-users(a)lists.wfu.edu
http://lists.wfu.edu/mailman/listinfo/gretl-users
--
Lee Adkins
Professor of Economics and Department Head
Economics and Legal Studies in Business
Oklahoma State University
Email: lee.adkins(a)okstate.edu
Fax: 405-744-5180
Phone: 405-744-5196
URL:
www.learneconometrics.com