Question

100万个零件,简单随机抽样不重复抽取1000个测验,测得废品率2%,如果以99.73%概率保证,求废品率的变化范

Answer 1

比例的抽样估计

n=1000,p=0.02,α=99.73%,Z(α/2)=2.99

废品率的变化范围

p=0.02±Z(α/2)*(p(1-p)/1000)^(1/2)=0.02±0.01323

=0.00677~0.03323