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: AW: Evaluating a set of conditions
From
"Martin Weiss" <[email protected]>
To
<[email protected]>
Subject
st: AW: Evaluating a set of conditions
Date
Wed, 23 Jun 2010 09:37:23 +0200
<>
The check for "missing<." strikes me as redundant, as this is a count of
missings and will range from 0 to 5 in your example. How could it be
missing?
Is it really correct to include "a" in your call -egen anytwo = rowtotal(a b
c d e), missing-. I thought "a" was supposed to be evaluated separately.
HTH
Martin
-----Ursprüngliche Nachricht-----
Von: [email protected]
[mailto:[email protected]] Im Auftrag von Thomas Speidel
Gesendet: Mittwoch, 23. Juni 2010 01:10
An: [email protected]
Betreff: st: Evaluating a set of conditions
Following up on my previous post:
http://www.stata.com/statalist/archive/2010-06/msg00984.html
here is an example for something I am trying to achieve in a
nice/efficient/eleganty way.
I have a number of dummies: a, b, c, d, e (missing values do exist)
Disease=true if the following conditions are met:
1) a must be true AND
2) any two of b, c, d, e are true
As I said missing values are crucial, especially when evaluating the
second condition.
My current program works, but I don't think it is efficient and it
probably does things that are unnecessary:
*******************************************
egen anytwo = rowtotal(a b c d e), missing
egen missing = rowmiss(a b c d e)
replace anytwo = . if (anytwo==0 & missing>=2 & missing<.)
replace anytwo = . if (anytwo==1 & missing==1)
replace anytwo = . if (anytwo==1 & missing==3)
replace anytwo = . if (missing>=4)
gen disease = 1 if (a==1 & anytwo>=2 & anytwo<.)
replace disease = 0 if (a==1 & anytwo<2)
replace disease = 0 if a==0
replace disease =. if a==.
*******************************************
I tried to play around with cond, but I found it was making this much
more complicated then it is. I know I am complicating my life more
than I need to which is why I am looking for alternative solutions.
--
Thomas Speidel
*
* 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/
*
* 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/