/*
This program will randomly select a four-by-four Latin square for
the tire wear experiment discussed in class.  The numbers 1 through
4 in the final table correspond to the four methods of tire
construction.
*/

proc plan; /* seed=435; */
  factors car=4 ordered position=4 ordered / noprint;
  treatments treat=4 cyclic;
  output out=one
    car cvals=('car 1' 'car 2' 'car 3' 'car 4') random
	position cvals=('left front' 'right front' 'left rear' 'right rear') random
	treat nvals=(1 2 3 4) random;
run;

proc print;
run;

proc tabulate;
  class car position;
  var treat;
  table car, position*(treat*f=6.) / rts=8;
run;