--- Marc Keuschnigg <[email protected]> wrote:
> I am estimating non linear least squares models (nl) using equations
> like: nl (y = ({a}+{b}* x) * (1-x)).
> My question is, how do I impose parameter restrictions like a >=0 and
> b >=0?
> I could log-transform the parameters, but I don't know how to do it
> technically within the nl command.
nl (y = (exp({a})+exp({b})* x) * (1-x))
-- Maarten
-----------------------------------------
Maarten L. Buis
Department of Social Research Methodology
Vrije Universiteit Amsterdam
Boelelaan 1081
1081 HV Amsterdam
The Netherlands
visiting address:
Buitenveldertselaan 3 (Metropolitan), room Z434
+31 20 5986715
http://home.fsw.vu.nl/m.buis/
-----------------------------------------
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