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From: Steven <ytsteven@gmail.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Help on fminsearch
Date: Sun, 8 Nov 2009 03:48:00 -0800 (PST)
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On Nov 8, 10:15 pm, "John D'Errico" <woodch...@rochester.rr.com>
wrote:
> Steven <ytste...@gmail.com> wrote in message <09b40b63-dab0-4d44-ae14-e078505de...@s31g2000yqs.googlegroups.com>...
> > Hi, all
>
> > I am a newbie and need some help on fminsearch. I worte this function
> > on cox proportional hazard model, and try to maximise the likelihood
> > on the coefficient of the covariates.
>
> > But the code doesn't work, it only sticks to thei nitial values of the
> > coefficients, ie. beta = ones(p,1) and won't do the optimisation.
> > Could anybody please help me on this? Many Thanks!!
>
> > function [logL] = myfun(beta)
>
> > load mydata
>
> > d = size(mydata);
> > n = d(1,1);
> > p = d(1,2)-2;
> > t = mydata(1:n,1);
> > ind = mydata(1:n,2);
> > z = mydata(1:n,3:p+2);
> > beta = ones(p,1);
>
> You do recognize that regardless of the value of
> beta as it is passed in, that this line will overwrite it?
>
> John- Hide quoted text -
>
> - Show quoted text -

Hi, John

Do you mean this line ----> beta = ones(p,1); ?

But without this line, I always have the error message like "beta is
undefined" or something...