selected towns. Villages－jpjzhf9的部落格

標題:

selected towns. Villages

發問:

200 randomly selected towns. Villages and 120 school children for investigation. Cities found that 90 school children. 30 villages suffering from myopia ... please test the city's children suffer from myopia rate is higher than that of rural school children (a = 0.05) also use ci again with????

最佳解答:

588 你好隨機抽取市鎮200名.和鄉村120名學童作調查.發現其中都市學童有90名.鄉村有30名患近視…請檢定都市學童患近視的比率是否高於鄉村學童(a=0.05)也請用ci再做一次是否符合???? (1) 這是兩母體比例差之檢定 H0: 都市學童患近視的比率等於或低於鄉村學童 H1: 都市學童患近視的比率高於鄉村學童都市學童患近視的比率=90/200=0.45 鄉村學童患近視的比率=30/120=0.25 混合估計值=(30+90)/(120+200)=120/320=0.375 標準誤=[(0.375*0.625/200)+ (0.375*0.625/120)]^0.5=0.0559 Z=(0.45-0.25)/0.0559=3.577817531 單尾，α=0.05，臨界Z值為1.645 因為Z=3.578>1.645，故拒絕H0 亦即在95%的信心水準下，都市學童患近視的比率顯著高於鄉村學童 (2)信賴區間法兩母體比例差之信賴區間為（(0.45-0.25)-1.96*0.0559，(0.45-0.25)+1.96*0.0559） =（0.09436，0.309564）區間內沒有包含0，故拒絕H0