st: event history and research design question

["andrew enterline" <ajenter@hotmail.com>]

Hello,

I have a sample of 213 civil wars.  My dependent variable of interest is 
civil war duration.  A subset of this sample 213 civil wars--18 civil 
wars--experience a third party intervention.   I measure several independent 
variables pertaining to these 18 cases with intervention.  Unfortunately, 
these independent variables are not measured for the 195 cases in which 
intervention did not occur.  However, I'd prefer to include the information 
for the dependent variable (i.e., the duration) for these 195 cases in order 
to serve as a benchmark against which to assess the intervention subset.  
One of my colleagues suggested using the -stset- command for "late entry" to 
retain this information on the dependent variable for these cases, but avoid 
including zeros for observations where the intervention variables are 
unmeasured.  Another suggestion was to drop an event history approach 
altogether in favor of testing differences of means for different subsamples 
in the data, but this approach has limitations as well.

Would anyone have any suggestions about how I might address this problem, or 
citations to similar designs in the literature?  I am open to any 
recommendations whatsoever.

thank you ahead of time,
Andrew Enterline

a.j.enterline
University of North Texas
Dept. of Political Science
Box 305340
Denton, TX 76203
(v) 940.565.2313
(f)  940.565.4818
email: ajenter@unt.edu
homepage: http://www.psci.unt.edu/enterline/enterline.htm





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