Here's another way to do it. I assume, unlike Martin, that *Date are
Stata date variables.
gen date = min(MathDate, EngDate)
bysort id (date) : ///
replace MathScore = MathScore[_n-1] if missing(MathScore)
by id: replace EngScore = EngScore[_n-1] if missing(EngScore)
by id: keep if _n == _N
Nick
[email protected]
Martin Weiss
============
If it is all about the results:
clear*
input id Year str10 MathDate MathScore str10 EngDate EngScore
1 2002 "" . "6/21/02" 85
1 2003 "06/20/03" 55 "" .
1 2004 "" . "" .
1 2005 "" . "" .
2 2002 "" . "" .
2 2003 "06/20/03" 40 "" .
2 2004 "05/31/04" 55 "" .
2 2005 "" . "6/15/05" 65
end
compress
list, noobs sepby(id)
/*
Not really necessary...
gen mathdate=date(MathDate, "DMY")
format mathdate %tdMonth_DD,_CCYY
gen engdate=date(EngDate, "DMY")
format engdate %tdMonth_DD,_CCYY
*/
collapse (lastnm) MathScore /*
*/ EngScore, by(id)
list, noobs sepby(id)
Meryle Weinstein, Ph.D.
=======================
I have a dataset that contains 4 records per student representing scores
on
tests taken in each year. Each student may or may not have taken the
exam
in a particular year, or may have taken the same test in multiple years.
I
want to create a dataset that has one record for each student that has
each
of the tests taken, regardless of year and if taken multiple times the
last
test results.
Here's what the file looks like
Id Year MathDate MathScore EngDate EngScore
1 2002 6/21/02 85
1 2003 06/20/03 55
1 2004
1 2005
2 2002
2 2003 06/20/03 40
2 2004 05/31/04 55
2 2005 6/15/05 65
I thought I could do a reshape wide but there are lots of cells with no
data, plus some cells with multiple data for the same student.
*
* 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/
