PSTR code for RATS

[Estefaniame]

Good evening
I am using the GTVD code for estimating PSTR models with RATS but I have a question. Is it possible to impose a condition for certain parameters? Following the GTVD procedure I can exclude the variables I think are not affected by nonlinearities, for instance, but in case I would like to impose the condition that the coefficient for the "linear part" (let's call it "pi") to be zero, how can I do that with this procedure? Is it possible?
Thank you very much beforehand.

[TomDoan]

Have you contacted Prof. Colletaz about that? He wrote the procedure.