11.1. () n , . , , p →0, n ∙ p = a , P n (k) .
, k n
P n (k)= pkqn-k= pk (1 - p) n-k.
P n (k)= pk (1 - p) n-k= pk (1 - p) n-k.
a = n ∙ p p = , , :
P n (k)= =
= =
= .
n →∞
= = [ .. ].
11.2. , p →0, a = n ∙ p 10. , a k.
, n . -.
11.3. ( -) 0 1, ..0< p <1, , A k n
P n (k) , , , q =1- p.
. , , .. = .
11.4. ( -) 0 1, .. 0< p <1, , k 1 k 2 n , :
P n (k 1, k 2) , , , , q =1- p.
, .. . .
11.5. p =0,8. , 75 100 .
- = = = 1,25. (1,25)= (1,25)=0,1826 .
P100(75) *0,1826 0,04565.
11.6. () 0,8. , 69 100 .
n =100, p =0,8, q =0,2, k 1 = 70, k 1 = 100.
- = = = 1,25, = = = 5. (-2,5)= - (2,5)= -0,4938, (5)=0,5, P100(70,100) (5) - (-2,5)=0,5+0,4938=0,9938
12.1. (ω), Ω . .. (ω): Ω→ .
12.2. . , Ω={(,),(,p),(p,),(p,p)}. -{0,1,2}.
|
|
ω | (,) | (,p) | (p,) | (p,p) |
(ω) | 2 | 1 | 1 | 0 |
.
12.3. F(x)=F X (x) , , X ,
F(x)=P{ X < x }=P{ X (-∞; x)}.
12.4. O x, F(x) , .
12.5. F(x) , .. , F(x) F(x).
, { }={ }+{ }, F()=F()+P{ }.
.. P{ } 0, F()>F().
12.6. , P{ }= F()F().
12.7. F(x) , 12.6 < < .
12. 8. F(x)=0; F(x)=1.
F(-∞)=P{ X < -∞ }=P(Ø)=0, F(+ ∞)=P{ X <+ ∞ }=P(Ω)=1.
12.9. F(x) ( F(x)=F()).
12.10. P{ X x }=1-F(x).
{ X <+∞ }={ X < x }+{ X x }, P{ X <+∞ }=P{ X < x }+P{ X x };
P(Ω)=1= F(x)+ P{ X x }, P{ X x }=1- F(x).