DATA LIST FREE / id numb .
BEGIN DATA
1 5 2 15 3 30
END DATA.


* Next loop 'expands' the data file.
LOOP cnt=1 TO numb.
        XSAVE OUTFILE='c:\temp\temp.sav' /KEEP id numb.
END LOOP.
EXECUTE.


GET
  FILE='c:\temp\temp.sav'.


COMPUTE draw=UNIFORM(1).
RANK
  VARIABLES=draw  (A) /RANK /PRINT=NO
  /TIES=MEAN .


* In next line, replace 30 by the desired sample size.
SELECT IF (rdraw<=30).
EXECUTE.