options ls=75;

data one;
   input cohort $ @;
   do subj=1 to 7;
      input y @;
      if cohort="I" then do; gender="W"; age="y"; end;
      else if cohort="II" then do; gender="M"; age="y";end;
      else if cohort="III" then do; gender="W" ; age="o";end;
      else if cohort="IV" then do; gender="M" ; age="o";end;
      old=(age='o');
      women=(gender='W');
      oldwomen=old*women;
      output;
   end;
cards;
I   221   213   202   183   185   197   162 
II   271   192   189   209   227   236   142 
III   262   193   224   201   161   178   265 
IV   192   253   248   278   232   267   289 
;
run;

proc glm order=data;
   class age gender;
   model y=age|gender;
   means age|gender;
   estimate "mu[AB]:interaction" age*gender -1 1 1 -1;
run;
endsas;

/*proc reg;
   model y=old women oldwomen/covb;
run;*/

/*proc means var;
   class cohort;
   var y;
run;endsas;
*/
proc glm; 
   class cohort;
   model y=cohort/clparm;
   estimate "simple effect of gender - young" cohort -1 1; 
   estimate "simple effect of gender - old" cohort 0 0 -1 1; 
   constrast "main effect of age   " cohort -1 -1 1 1;
   constrast "main effect of gender" cohort -1 1 -1 1; 
   constrast "interaction effect   " cohort -1 1 1 -1;
   estimate "main effect of age   " cohort -1 -1 1 1/divisor=2;
   estimate "main effect of gender" cohort -1 1 -1 1/divisor=2; 
   estimate "interaction effect   " cohort -1 1 1 -1;
run;

proc glm;
   class age gender;
   model y=age|gender/solution ss1 ss2 ss3 ;
   estimate "mu[AB1]" age -1 1 gender*age -1 0 1 0;
   output out=two p=ymean;
   lsmeans age|gender/tdiff;
   *means age*gender;
run;

*goptions colors=(black) dev=pslepsf;
*goptions colors=(black); 

symbol1 i=join l=1 value=dot;
symbol2 i=join l=2 value=dot;

proc gplot;
   title "interaction plot";
   plot ymean*age=gender;
run;
quit;