Hble BeJIHqHHbI X
I
,X
2
"",X
n
He3aBHCHMbI,
TO
Kax,n;aH H3
3THX
C.rryqaUHbIX BeJIHqHH HMeeT paCrrpe.lleJIeHHe
KOll!H.
3.
ECl!H c.rryqaUHbIe BeJIHqHHbI X
I
,X
2
"",X
He3aBHCHMbI
H
n
pacrrpe.lleJIeHbI rro 3aKoHY
KOlllH
C rrapaMeTpaMH Ili> Ai
(i
=
1,
2,
...,n),
n
TO
c.rryqaUHaH BeJIHqHHa X =
La,X,
+ b
rro.n:qHHHeTCH
3aK0HY
KOIlIH
;;1
n n
C rrapaMeTpaMH Il =
La,ll,
+ b H A= L
la,IA;.
HHbIMH
CJIOBaMH,
JIH-
;;1
';1
HeUHaH
<PYHKI.J;IDI
c.rryqauHhIX BeJIlfllJm, pacrrpe.lleJIeHHbIX rro 3aK0HY
KOIIIH, HMeeT pacrrpe.lleJIeHHe
KOlllH.
4. C.rryqaUHaH BeJIHqHHa Y =
1/
X,
06paTHaH c.rryqauHou BeJIH-
qHHe
X,
pacrrpe.lleJIeHHOU rro 3aKoHy
KOIIIH
C rrapaMeTpaMH
)l,
A,
TaIOKe
HMeeT pacrrpe.lleJIeHHe
KOIIIH
c rrapaMeTpaMH Il' =
Il/(
11
2
+ A
2
)
H A'=A/()l2 +A
2
).
5.
IlycTb
Ix
(y)
H
Xx
(t) -
IVIOTHOCTb
BepOHTHOCTH
H
xapaK-
TepHCTHqeCKaH
<PYHKIJ:HH
CJIyqaHHOH BeJIJilqHHbI
X,
HMeIOmeH
pac-
rrpe.lleJIeHHe
KOIIIH
C rrapaMeTpaMH Il =
0,
A=
1;
In
(x) H
Xn
(1)
-
IIJIOTHOCTb
BepOHTHOCTH
H xapaKTepHCTHqeCKaH
<PYHKIJ:HH
CJIyqaH-
HOU
BeJIHqHHbI Y, HMeIOmeu pacrrpe.lleJIeHHe JIaIIJIaca C rrapaMeT-
paMH
Il =
0,
A =
1.
TOf.lla CrrpaBe.llJlHBbI
CJIe.llYIOmHe
COOTHOIlleHHH:
Ix
(x)
==
-
1
Xn
(x)
H
Xx
(1)
==
21
(1).
n
rt
6.
ECJIH CJIY'lauHbIe
BemNHHbI
X
I
,X
,,,,,X
He3aBHCHMbI H
2
n
HMeIOT
O.llHO
H
TO
)Ke
pacrrpe.lleJIeHHe KOIIIH,
TO
HX
Cpe.llHee apH<p-
MeTHqeCKOe
(XI
+ X
2
+
...
+ Xn
)/n
HMeeT TaKOe)Ke pacrrpe.lleJIe-
HHe, KaK H Kax,n;aH
H3
c.rryqaHHbIX BeJIHqHH
X,
(i
=
1,
2,
..., n).
Ta-
KHM
o6pa30M,
C TOqKH 3peHHH
Ou;eHHBaHHH
napaMeTpa nOJIO)Ke-
HHH
)l
Cpe.llHee apH<pMeTINeCKOe He 60JIee HH<popMaTHBHo, qeM
JII06aH H3 c.rryqauHblX Bel!HqHH
XI>
X2 ,
...
, X n •
7.
ECJIH
X H Y He3aBHCHMbI H HMeIOT
O.llHO
H
TO
)Ke
pacrrpe.lle-
JIeHHe
KOIIIH,
TO
CJIyqauHbIe BeJ!HqHHbI X + X H X + Y HMeIOT
O.llHO
II
TO
)Ke
pacrrpe.lleJIeHHe KOIIIH.
3TO
yrBep)f{JleHHe CrrpaBe.ll-
JIHBO
H.llJIJI CJIY'laUHblX BeJIHqHH:
aX
+
bY,
(lal+lbl)X
H
([al+lbI)Y.
1',1
8.
Pacnpe.lleJIeHKe
KOIIIH
C rrapaMeTpaMH
Il
==
0,
A=1
COBna,l(aeT
.'
C pacrrpe.lleJIeHHeM CTbIO.lleHTa C napaMeTpoM v
==
1.
9.
C.rryqaHHaH BeJ!HqHHa
X:;::)l
+ A
tg<I>,
f.lle
<I>
- CJIyqaHHaH Be-
JIJilqHHa, pacnpe.lleJIeHHaH paBHoMepHo B HHTepBan:e
(-
1t/2, rt/2),
HMeeT pacrrpe.lleJIeHHe
KOIllII
C napaMeTpaMH Il, A (pHC. 3.4).
A
o
Il
x x
PRC.
3.4.
BepollTHoCTHllJI
cxeMa.
IIpHBO.llJllllllJl K pacnpe,ll;eJIeH1UO
KOlli.\{.
114
O~eHMBaHMe
napaMeTpoB
O:u;eHKH
napaMeTpOB Il, A pacnpe.lleJIeHllil
KOilIH
onpe.lleJIHIOTC$!
C nOMOIUbIO BbI6opOqHblX
KBaHTHJIeM
x;
:
x
p
•
ctg
(1tP
I
) -
x
p
•
ctg(
rtP2).
x
p
' - x
p
•
Il
==
' I • A
==
' 1
ctg
(rtPI) -
ctg
(1tP2)'
ctg
(7tPI)
-
ctg
(7tP2)
f.lle
x;,
- BbI60pOQHaH KBaHTHJIb
nOPMKa
P;
, i
==
1,
2.
B «CHMMeTpHqHOM» c.rryqae,
T.
e.
npH
PI
==
P < 0.5 H
P2
=
1-
p:
•
x;+P;_p
•
(x;_p-x;)tg(rtp)
(1)
Il
==
2 ' A:;:: 2
IlpH
P = 0.25
<pOPMYJIbI
(1) npHHHMaIOT
oco6eHHo
npocTou
H
HafJIMHbIH
BM:
•
X~.25
+
X~.75
A.
=
X~.75
-
X~.25
Il=----
2 2
f.lle
X~.25
H
X~.75
- Bbl6opOqHble
o:u;eHKH
rrepBoM H TpeTbeH KBapTH-
JIeM
CJIyqaMHoH BeJIHqHHbI
X.
B KaqeCTBe 3THX
o:u;eHOK
HCrrOJIb3y-
IOTC$!
3JIeMeHTbI
ynoPMOqeHHOU
BbI60PKH
061>eMa
n C HOMepaMH
L(n +
2)/4)J
H L(3n + 2)/4J.
reHepMpOBaHMe
cny'laMHblx
'1MCen
x,
:;::
Il + Atg (21tr,).
3.4.
PACnPEAE11EHME 3KCTPEMAJ1bHOro 3HA'fEHMR
1
3.4.1.
PACnPEAE11EHME MMHMMAJ1bHOrO 3HA'fEHMR
IlJIOTHOCTb
BepO$ITHOCTH
<I>YHKIJ:HH
pacnpe.lleJIeHHH
<I>YHKIJ;HH
f(x)
=
iexp
( x
~
Il
-
e(X-tJ.)/Io.).
-00
< x <
00,
f.lle Il - napaMeTp
nOJIO)KeHHH
(Mo.n;a); A -
rrapaMeTp MacIIITa6a
(A
>
0)
F(x)
=
1-
exp
(--e(X;t)!Io.)
1
A(X) = -e(X;t)/lo.pHcKa
A
I B HeKOTOpbIX PYKOBOACTBax
paCCMaTpHBaeMoe
pacnpeAeJIeHHe
Hll3blBaeTClI
pacnpeoelleHueM 3KCmpeMallllHOZO :matteHWI
muna
1,
HIIH
pacnpeOeJleHUeM 'JKcmpe-
MallllHOZO 3HatteHWI ry.w6eJUl.
115