st: RE: RE: Fillin missing values, probability for new value

["Maarten Buis" <M.Buis@fsw.vu.nl>]

Hi Pamela,

A colleague recently told me about an interesting technique
of dealing with this problem, that at first glance sounds nice, 
but I have no idea about the statistical properties. Basically 
for each observation with a missing you add two 
observations: one with value 1 and one with value 2 and 
you attach to the first observation a weight equal to prob1 
and to the second a weight equal to prob2. All complete 
observations receive a weight of 1. Again, it sounds nice to 
me, but if anyone else on statalist warns you not to use it, 
than I will bow to superior wisdom. 

HTH,
Maarten

-----------------------------------------
Maarten L. Buis
Department of Social Research Methodology 
Vrije Universiteit Amsterdam 
Boelelaan 1081 
1081 HV Amsterdam 
The Netherlands

visiting adress:
Buitenveldertselaan 3 (Metropolitan), room Z214 

+31 20 5986715

http://home.fsw.vu.nl/m.buis/
-----------------------------------------

Pamela Mueller wrote:
 I  need to fill in missing values in my dataset. For most sectors I know
how many start-ups there were for each year, but the data was not given
if the number of startups (st) is less than 3 (hence one or two).
Therefore, I know if the missing is 1 or 2 and I know the probability
for either one. I also know how often 1 or 2 should be each given in
total for each year.
 
for each year and region the data looks like this:
sect         st         prob1      prob2
1             4
2             3         
3             .            0.3           0.7
4             8
5             0
6              .           0.45         0.55
7             3
8             5
9              .           0.48         0.52



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