Mo(X) X ( ( ) ( ) ).
, , , , .
Me(X) X , P(X<Me(X)) = P(X>Me(X))=1/2, . . , X , Me(X) , 1/2. x=Me(X), , Me(X), . , x=Me(X) ½, . . F(Me(X))=1/2.
() q ( q-) xq , , q, . . F(xq)=P(X<xq)=q.
, 0,5 (2- ), . . Me(X)=x0,5. x0,25 x0,75 (1- 3- ) .
k- X k- mk=M(Xk).
k- X k- X . mk=M[X-M(X)]k.
: xi - , pi, f(x) - , - .
, k=1 X m1=M(X)=a, k=2 - mk=D(X).
:
m1 = 0
m2 = m2 - (m1)2
m3 = m3 - 3m1m2 + 2(m1)3
m4 = m4 - 4m1m3 + 6(m1)2m2 - 3(m1)4
( ) .
() .
() . . , . . , =0. (>0), - (<0).
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( ) .
( ) ( 3 , . . ). , , , - .