* ======================================================================= 
*  File:  	median_across_columns.txt .
*  Date:  	26-May-2004 .
*  Author:  	Bruce Weaver, weaverb@mcmaster.ca .
*  Notes:	Show how to get median across columns.
* ======================================================================= .

* SPSS does not have a function for computing the median across columns.
* One work-around solution is to restructure the file from WIDE to LONG,
* then use the MEDIAN function available under AGGREGATE.  This method
* is demonstrated below.

* Restructuring of the data file is done using VARSTOCASES.
* If you are using an earlier version of SPSS that does not have
* VARSTOCASES, then you will have to restructure the file the old-
* fashioned way, as shown in this file:
* http://www.angelfire.com/wv/bwhomedir/spss/restructure_old.txt .


* Read in some data .

data list list / id v1 to v5 (6f1.0).
begin data.
1    1   1   1   4   3 
2    2   2   3   5   1 
3    2   2   3   1   1 
4    1   3   3   3   5  
end data.

VARSTOCASES 
 /MAKE score FROM v1 to v5
 /INDEX = index(5)
 /KEEP =  id
 /NULL = drop.

aggregate outfile = *
 /presorted
 /break = id
 /median = median(score).

list.

* Use MATCH FILES to merge with the original data file if necessary.

* End of job.

* ======================================================================= .