标题: a wording problem [打印本页] 作者: ashycal 时间: 2011-7-13 13:34 标题: a wording problem
when practice question say: a study was conducted to determine whether the standard deviation of monthly costs of PA company is $300, why the correct null hypothesis H0= standard deviation of the population=300, it really sounds like Ha=300???作者: invic 时间: 2011-7-13 13:34
Also, in chi-square problem, when the H0>16, Ha<16, DF=23, significant level=0.05, why i should look at the 0.95 column(yes, 95% probability in the right tail), and reject the null if chi-square is less than the critical value? why less than?
