st: sampling problem

["John allfish" <j_w11111@hotmail.co.uk>]

I have been trying a number of ways of sampling. I want to use the samplepps 
command which has the following syntax:

samplepps newvar, withrepl size(varname) ncases(integer)

What I want to do is to create a program which will run this command several 
times. The problem is that I want the ncases(integer) to be different. I 
have a vector of values which I want ncases to take on. So I run I may have 
5 different values in my vector. I want to run samplepps five times with 
ncases taking on the value of the first row of the vector for the first 
time, the second row the second time and so on.

Is there any quick way of doing this or do I just have to manually enter the 
number each time?

Thank you,
John




I want to sample data on the basis of counterfactuals - so what would the 
distribution of income in 2007 look like if individuals had the distribution 
of health of 1985.

So imagine I have the following data

id           income2007          health2007             health1985          
wgt1985
1                 10                      1                              1   
                65.38
2                 10                      1                              1   
               153.91
3                 20                      1                              1   
               458.34
4                 20                      1                              1   
               484.2
5                 40                      2                              1   
               906.1
6                 40                      2                              4   
               943.96
7                 60                      4                              5   
             1176.87
8                 60                      4                              5   
             1389.91
9                100                     5                              5    
            1716.93
10              100                     5                              5     
           4067.68

where weight is the sampling weights for the 1985 data (I also have sampling 
weights for the 2007 data). The order of the 1985 data makes no difference 
to the 2007 data it is just pasted in to obtain the health distribution.
What I want to do is sample from the 2007 data to make the distribution of 
health in 2007 look like that in 1985. So I want to draw individuals from 
2007 according to the distribution of health in 1985 so I draw individuals 
with health=1 with prob=0.4, health=2 with prob=0, health=4 with prob=0.1 
and health=5 with prob=5 (where the probabilities comes from the health1985 
distribution). This should give me a hypothetical distribution of income in 
2007 if the distribution of health was as in 1985.
I cannot see how to do this with the bsample command. Further I am not sure 
then how to incorporate the sampling weights to ensure that my samples 
correctly represent the population distributions.
Any help would be much appreciated.
Yours,
John

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