T分布
累積分布関数:
F ( t ) = 1 2 [ 1 + t 2 + t 2 ] . {\displaystyle F(t)={\frac {1}{2}}\left[1+{\frac {t}{\sqrt {2+t^{2}}}}\right].}
確率密度関数:
f ( t ) = 1 ( 2 + t 2 ) 3 / 2 . {\displaystyle f(t)={\frac {1}{\left(2+t^{2}\right)^{3/2}}}.}