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Re: st: can cond() be nested (within nl)?
From
David Raitzer <[email protected]>
To
"[email protected]" <[email protected]>
Subject
Re: st: can cond() be nested (within nl)?
Date
Tue, 4 Dec 2012 00:09:53 +0800 (SGT)
What I mean is something like this: nl ( y = cond(x <={z}, cond( x <= {k}, {a}*x + {b}, {c}*x + {k}*( {a} - {c}) + {b} ) ) , {s}*x + {z}*( {a} - ({c}+{s})) + {b} ) , initial (a 1 b 1 c 1 k 1 s 1 z 1)
However, it doesn't seem to work for me. Is it not possible to nest cond in this manner within nl? Thank you for your help.
----- Original Message -----
From: Nick Cox <[email protected]>
To: [email protected]
Cc:
Sent: Monday, December 3, 2012 6:39 PM
Subject: Re: st: can cond() be nested (within nl)?
It is perfectly legal to include -cond()- within the <sexp> in
nl (depvar=<sexp>) [if] [in] [weight] [, options]
if that is what you mean. But -mkspline- followed by -regress- sounds
much easier here.
On Mon, Dec 3, 2012 at 9:59 AM, David Raitzer <[email protected]> wrote:
I am trying to do a segmented linear regression with the nl function
and cond. The intention is to have two breakpoints and 3 segments,
which means that 3 conditions are required. Can cond be nested
within nl to apply more than 2 conditions? If not, what is the best
way to approach such a regression when the segmentation depends upon 3
ranges of an x, rather than only 2? Thanks!
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