Date:         Tue, 15 Jul 2008 09:01:27 -0500
Reply-To:     Mary <mlhoward@avalon.net>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Mary <mlhoward@AVALON.NET>
Subject:      Re: How to create all possible response patterns?
Comments: To: "Kevin F. Spratt" <Kevin.F.Spratt@DARTMOUTH.EDU>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
              reply-type=response

Getting the number of permutations and then running it through Proc Plan
will do this; I believe you'd want both parameters to be 3 rather than one
to be 2.


%let c = %sysfunc(perm(3,2));
%put &c;

ods output Plan=out_set;
proc plan;
    factors Block=&c2 ordered
    Treat=2 of 3 perm;
run;

-Mary
----- Original Message -----
From: Kevin F. Spratt
To: SAS-L@LISTSERV.UGA.EDU
Sent: Tuesday, July 15, 2008 8:06 AM
Subject: How to create all possible response patterns?


Suppose I have a 3 item survey.

Each item can have a value of 1, 2, or 3.

If I wanted to create all possible response patterns in this case the
possible patterns are 3^3 = 27

1 1 1
1 1 2
1 1 3
1 2 1
1 2 2
1 2 3
1 3 1
1 3 2
1 3 3
2 1 1
2 1 2
2 1 3
2 2 1
2 2 2
2 2 3
2 3 1
2 3 2
2 3 3
3 1 1
3 1 2
3 1 3
3 2 1
3 2 2
3 2 3
3 3 1
3 3 2
3 3 3
;

How do I automate this process in a fashion that scales to the case
where the number of items
is 10, thus generating 3^10 unique patterns?

I thought that there may be an SQL general solution, where you create
10 data sets each
having a single variable (item name) with the full range of choices,
but I have not been
able to successfully create this table.

As always, any help appreciated.

I'm running 9.1.3 on Windows XP today, 9.2 tomorrow!







______________________________________________________________________

Kevin F. Spratt, Ph.D.
Department of Orthopaedic Surgery
Dartmouth Medical School
One Medical Center Drive
DHMC
Lebanon, NH   USA  03756
(603) 653-6012                          (voice)
(603) 653-6013                          (fax)
Kevin.F.Spratt@Dartmouth.Edu            (e-mail)
_______________________________________________________________________