2.2.
PACnpE,q,E1T£HME
nYACCOHA
x
PH.D;
pacnpe,neJIeHWI
p(X) =;
e-I',
X =
0,1,
2,
...
,
x.
r,ne
napaMeTP Il - MaTeMaTHqeCKOe o)l(JfJla-
HHe
(J.1
> 0)
O,
X
~
0;
<1>YHKUWI
F(x)
= e-I' ±Il
i
k < X
~
k +
1,
{
pacnpe,neJIeHWI
i:O
i!'
k =
0,
1,
2,
...
ITpoH3BOWlmaH
<p
x
(t)
=
el'(t-l)
=
exp
(Il(t
-
1»)
cl>YHKUWI
XapaKTepHCTlflIeCKaH
X.X
(t)
= exp (Il(e
il
-
1»)
cl>YHKUIDI
MaTeMaTHqeCKOe
X = Il
O)l(JfJlaHHe
LIl
J,
Il - He ueJIoe;
Mo,na
-I},
x= :
Il-
ueJIoe
{
AHcnepcWI
D
x
=
Il
CTaH,napTHOe
CJ
x
=
~
OTKJIOHeHHe
1
K03cl>cl>HUHeHT
v
=-
BapHaUHH
x~
Sk=_1
ACHMMeTPWI
~
1
3Kcuecc
Ex
=-
Il
HaqaJIbHble
m
2
=
Il
+
1l
2
;
MOMeHTbI
m
l
=
Il
+
311
2
+
Ill;
2
3
4
m
4
= Il +
711
+
611
+
11
2
UeHTPaJIbHble
III
=Il;
114
=Il+
31l
;
MOMeHTbI
Oil
Il.
=
(S-I)IlIl._2
+Il
0;1
p(x)
p(x)
0.4
0.4
J.l
> I -
He
ueJloe
0<J.l<1
J.l= 0.9
1
J.l
=
1.8
0.3
0.3
0.2 0.2
O.L
0.1
x
-
o 2
3
4
5 x
0
1 2
3
4 5
6
7 x
"
"
x
x
p(x)
l
0.2
•
•
J.l>
1-
ueJloe
J.l=3
0.1
0
I 2
3
4 5 6
7 8 9 x
" "
xI
x2
PHC.
2.2.
l1>yHKUIDI
BepOJITHOCTH
pacnpe.lleJleHIDI IIyaccoHa.
THnHqHaH
HHTepnpeTaUHH:
X -
qHCJIO
C06bITHii CTaUHO-
HapHoro
op,nHHapHoro nOTOKa 6e3 nOCJIe,neiiCTBWI (nyaccoHoBCKO-
ro
nOTOKa) B HHTepBaJIe cl>HKcHpoBaHHOii AJIHHbI; Il - MaTeMaTH-
qeCKOe O)l(JfJlaHHe
qHCJIa
C06bITHii (Cpe,nHee
qHCJIO
C06bITHii) B
paCCMaTPHBaeMOM HHTepBaJIe (pHC.
2.2).
COOTHoweHMA
Me)KAY
pacnpeAeneHMAMM
1.
CYMMa S He3aBHCHMbIX nyaccoHoBCKHX CJIyqaiiHbIX BeJIHqHH C
napaMeTPaMH
Ill'
1l2"'"
Il.
no,nqHHHeTCH 3aKoHy
ITyaccoHa
C
na-
paMeTPOM Il =
III
+
112
+
...
+
Il
•.
CnpaBeAJIHBO H o6paTHoe yTBepJK-
,neHHe:
eCJIH
CYMMa
He3aBHCHMbIX CJIyqaiiHbIX BeJIIflIHH pacnpe,ne-
JIeHa
no
3aKoHy
ITyaccoHa,
TO
KaJK,noe
CJIaraeMOe pacnpe,neJIeHO
no
3TOMY
JKe
3aKOHY.
2.
Pacnpe.lleJIeHHe
ITyaccoHa
TeCHO
CBH3aHO
C nOKa3aTeJIbHbIM
(3KcnoHeHUHaJIbHbIM) pacnpe,neJIeHHeM H pacnpe,neJIeHHeM
3p-
JIaHra. ITYCTb T
I
,
T
2
,
•••
, T
m
-
MOMeHTbI nOHBJIeHWI C06bITHii CJIy-
qaiiHOrO nOTOKa, HanpHMep nOTOKa COo6meHHii, OTKa30B H
T.
n.;
XI
X
2
,
•••
, X m - CJIyqaiiHble npOMeJI(yTKH BpeMeHH
MeJK.nY
3THMH
C06bITWIMH;
N(t)
-
qHCJIO
C06bITHii CJIyqaiiHoro nOTOKa B
cl>HKCH-
pOBaHHOM HHTepBaJIe BpeMeHH
[0,
t] (pHC. 2.3).
N(t)
(
r-
Xt
r
Xr
1c
r
Xm
1c
-
~
!
~
o t
T.
T
2
T
m
-
I
T,n
PHc.
2.3.
IIyaccoHoBcKHA
nOTOK
CJIY'laAHhlX
C06hITHH.
KpecmUKaMU
0603HaQeHhI
C06h1TIDI
cJIY'l:aAHOrO
nOTOKa.
43·
42