data walk;
input trtment time;
label trtment='treatment group' 
      time='ages (in months)';
lines;
1 9.00
1 9.50
1 9.75
1 10.00 
1 13.00
1 9.50
2 11.00
2 10.00
2 10.00
2 11.75
2 10.50
2 15.00
3 11.50
3 12.00
3 9.00
3 11.50
3 13.25
3 13.00
4 13.25
4 11.50
4 12.00
4 13.50
4 11.50
run;

proc format;
 value trtment 1='active'
                 2='passive'
                 3='no-exercise'
                 4='control';
run;

proc glm;
  class trtment;
  model time=trtment;
  means trtment/dunnett ('control');
  means trtment/tukey scheffe lines;
format trtment trtment.;
title 'Example of One-Way ANOVA';
title2 'Data from Table 10.1, P. 420 of Fisher and van Belle';
run;

proc plot;
 plot time*trtment;
 title 'Distribution of Ages at which Infants First Walked Alone'; 

run;