st: sampling program help

[george joseph <gjosephresearch@gmail.com>]

  Hi,
I would like to have your help with writing a program to resolve  the
following sampling issue I have
I have data on 223 sansads  ( sansad_id) in 19 GPs . The variable
prone_flood_cyclone (1-4) indicates
the strength of floods and cyclones in the sansads and tot_sansads
indicates the total number of sansads in each GP.

I would like to draw a sample of 55 sansads in the following manner.
1) The sample should contain sansads from all 19 GPS
2) If the  total number of sansads (tot_sansads) in a GP is less than
12, we should draw one sansad, if  tot_sansads is between 13 and 14,
we should draw 2 sansads, if  tot_sansads is between 15 and 16,  we
should draw 3 sansads, and if  tot_sansads is between 17 and 20, we
should draw 4 sansads.

The following is the METHOD OF ALLOCATION of the number of SANSADs in
each of the  GPs giving OVER-WEIGHTAGE to SANSADs Prone to floods,
cyclones etc.
If the
Total number of SANSADs in one GP   :8-12
Number of SANSADs   to be selected : 1
Method of Allocation ( based on ne_flood_cyclone)
      1 to be selected from Code’4 ‘. If Code 4 is ‘NIL’, than 1
from Code ‘3’. If Code 3 is also’ NIL’,   then 1 from Code’2’. If Code
2 is also ‘NIL’, then 1from Code ‘1’.

if
Total number of SANSADs in one GP   :13-14
Number of SANSADs   to be selected : 2
Method of Allocation ( based on prone_flood_cyclone)
      1 from Code ‘4’+from Code’3’ – otherwise, follow the sequence
as in sl.1.
if
Total number of SANSADs in one GP   :15-16
Number of SANSADs   to be selected : 3
Method of Allocation ( based on prone_flood_cyclone)
      1from Code’4’ +1from Code’3’+1 from Code’2’- otherwise, follow
the sequence as in sl.1.
and if
Total number of SANSADs in one GP   :17-20
Number of SANSADs   to be selected : 4
Method of Allocation ( based on prone_flood_cyclone)
      2from Code’4’+1 from Code’3’+ 1from Code’2’+1 from Code’1’-
otherwise, follow the sequence as in sl.1.

Could you let me know how I can do this which can be replicated .
Thanks.
George

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