% ch8example14prog.m
clear;
alpha=[0.1, 0.05, 0.01]
pn=[1 10 100 1000 10000 100000]';
for i=1:3
    r(:,i)=sqrt(2./pn).*erfinv(1-alpha(i));
end
loglog(pn,r);
legend('\alpha =0.1 ','\alpha =0.05 ','\alpha =0.01 ');    
xlabel('多次試驗中事件發(fā)生的次數(shù) np ');
ylabel('相對精度 r');