data example;

seed=123;do n=5,10,20,30;

do j=1 to 1000;

do i=1 to n;

x=0.5746*normal(seed)+4.6602;

output;

keep i j n x;

end;end;end;run;

proc means data=example mean;

var x;

class n j;

output out=amean=mean;

run;

data b;seta;set example;

proc chart data=b;

hbar mean;by n;

run;

我想画各种样本量的样本均数的频数分布图，就是要出4个图。谢谢各位！