Notice: On April 23, 2014, Statalist moved from an email list to a forum, based at statalist.org.
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
st: RE: nl-function log4-formula
From
Nick Cox <[email protected]>
To
"'[email protected]'" <[email protected]>
Subject
st: RE: nl-function log4-formula
Date
Wed, 16 Nov 2011 10:36:08 +0000
I don't know, but tucking the -if- condition inside the parentheses looks a bit odd. Try moving it outside.
-nl- is a command, not a function.
Nick
[email protected]
Jennyfer Wolf
I am working with the nl-function and with the logistic function model log 4.
Could somebody please explain me why I do not get the same outout if I type:
1. nl log4: VAR1 VAR2 if VAR3=="xxx"
and
2. nl(VAR1={b0}+{b1}/(1+exp(-{b2}*(VAR2-{b3}))) if VAR3=="xxx")
Actually 1. should just be an abbreviation of 2.?
If I run command 1, I get estimates for b0, b1, b2, b3, if I run
command 2 I only get an estimate for b0 and b1-b3 are 0.
Could somebody explain how to write the formula "in full" (like in
2.), to get the same results as in the first formula.
*
* For searches and help try:
* http://www.stata.com/help.cgi?search
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/