options ls=80;
data;
    pi=.75;
    n=56;
    alpha=.05;
    df=1;
    cv=cinv(1-alpha,df);
    do p=.01 to .99 by .01;
        ncp=n*((p-pi)*(p-pi)/pi+(p-pi)*(p-pi)/(1-pi));
        power=1-probchi(cv,1,ncp);
        output;
        end;
proc print;
    var n pi cv p ncp power;
run;
symbol1 i=j;
proc gplot;
    plot power*p;
    run;