p值：反映某一事件发生的可能性大小
单侧检验和双侧检验：
z test：n<30 Z = (T − θ) / s
t test: n>30
{\displaystyle t={\frac {Z}{s}}={\frac {{\bar {X}}-\mu }{{\widehat {\sigma }}/{\sqrt {n}}}}}
Type1 error:false positive -- i.e. you falsely reject the (true) null hypothesis.
Type2 error:the non-rejection of a false null hypothesis (also known as a "false negative" finding or conclusion)
均值之差的假设检验
T=Y1¯−Y2¯s21/N1+s22/N2√
p值：反映某一事件发生的可能性大小 单侧检验和双侧检验： z test：n<30 Z = (T − θ) / s t test: n>30 {\displaystyle t={\frac {Z}{s}}={\frac {{\bar {X}}-\mu }{{\widehat {\sigma }}/{\sqrt {n}}}}} Type1 error:false positive -- i.e. you falsely reject the (true) null hypothesis. Type2 error:the non-rejection of a false null hypothesis (also known as a "false negative" finding or conclusion) 均值之差的假设检验 T=Y1¯−Y2¯s21/N1+s22/N2√