[S] minimizing multi-parameter functions?

Bill Shipley (bshipley@courrier.usherb.ca)
Wed, 18 Mar 1998 09:33:01 -0500


I want to find values of a vector of parameters q=(a,b,c,d) that minimizes a
function foo(q,X) where X is an additional argument. This is supposed to be
done using the nlminb() function; i.e.
nlminb(start=q0,foo,X=my.X)

However, I have found that this does not find the minimum very well for my
function. I suppose that this is because the algorithm is getting stuck in
a local minimum. Is there a better (safer) way to do this?
Bill Shipley
Departement de Biologie
Universite de Sherbrooke
Sherbrooke (Quebec)
CANADA J1K 2R1
bshipley@courrier.USherb.ca
voix: 819-821-8000 poste 2079
telecopieur: 819-821-8049
Visitez notre site WEB : http://www.usherb.ca/SCES/BIO/index.html

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