Date:         Mon, 22 May 2006 21:09:58 -0400
Reply-To:     Ei-Wen Chang <ei-wen_chang@CTB.COM>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Ei-Wen Chang <ei-wen_chang@CTB.COM>
Subject:      random delet from subgroups

I have to random delete some observations in subgroups from a master data
(STD).  The rules are like following.

If form='A1', grade=2, ethnicity=H or I then random delete 5 cases from
this subgroup.
If form='A1', grade=3, ethnicity=B then random delete 9 cases from this
subgroup.
If form='A3', grade=2, then random delete 8 cases from this subgroup. (no
target ethnicity)
If form='A3', grade=7, and ethnicity='A' then random delete 6 cases from
this subgroup.

There are more form, grade, and ethnicity combinations that needs to be
excluded, so I don't want to hard code.  If anyone can give me some
advices, I will appreciate your help.  Following are my sample data.

data excluse;
infile cards missover;
input @1 form $2. @4 grade @6 ethnicity $2. @9 del_n;
cards;
A1 2 HI 5
A1 3 B  9
A3 2    8
A3 7 A  6
;


Data std;
do i=1 to 20;
 form='A1';
 grade=2;
 ethnicity='H';
 output;
  form='A1';
 grade=2;
 ethnicity='I';
 output;
 form='A1';
 grade=3;
 ethnicity='B';
 output;
  form='A1';
 grade=3;
 ethnicity='I';
 output;
  form='A3';
 grade=2;
 ethnicity='A';
 output;
   form='A3';
 grade=2;
 ethnicity='I';
 output;
  form='A3';
 grade=7;
 ethnicity='A';
 output;
  form='A3';
 grade=7;
 ethnicity='A';
 output;
   form='A3';
 grade=7;
 ethnicity='B';
 output;
end;
run;


Ei-Wen