HAL Id: inria-00115528
https://hal.inria.fr/inria-00115528v4
Submitted on 23 Nov 2006
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A Bayesian analysis of industrial lifetime data with Weibull distributions
Nicolas Bousquet
To cite this version:
Nicolas Bousquet. A Bayesian analysis of industrial lifetime data with Weibull distributions. [Research Report] RR-6025, INRIA. 2006, pp.24. �inria-00115528v4�
a p p o r t
d e r e c h e r c h e
Thème COG
INSTITUT NATIONAL DE RECHERCHE EN INFORMATIQUE ET EN AUTOMATIQUE
A Bayesian analysis of industrial lifetime data with Weibull distributions
Nicolas Bousquet
N° 6025
Novembre 2006
Unité de recherche INRIA Futurs
/1
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∂hW(t|η, β)
∂t = β(β−1)
η2 t
η β−2
o`auso`_`baK_o`]C]MMg+o"Z\b^7a1]o`a0qM'L?MCo7XrKg\MCsWV
∂2hW(t|η, β)
∂t2 = β(β−1)(β−2) η3
t η
β−3
.
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β π(β) = Γ(p+q)
Γ(p)Γ(q)
(β−βl)p−1(βr−β)q−1
(βr−βl)p+q−1 [βl,βr](β)
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β 4 =^`KZ ZiHKM]^`L?pq^7aKMa{Z
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t0
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t1 > t0
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1−p1
1−p0
= exp (
−µxβ0 x1
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β
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= (1−p0)
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η 4 HWV{p=Mgi
puo`g\o`L?MZiMCg
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η ZiHuMt_`MauMg+ob¦CMCs baW`MCg\XiMk_{oL?LoOsKbXrZig\buYZib^`a
η|β ∼ GIG(a, b, β)
bZiH¸sYMCauXrbZ[V
f(η|a, b, β) = baβ Γ(a)
1 ηaβ+1exp
− b ηβ
1[0;+∞[(η) ²z7³
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l
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o`ausL@^YsYM2,
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X ∼ GIG(a, b, β)⇒
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`Mg\V #MCo`pKgi^7uoubbcZ[V ZiHuoZoabausKuX[Z\gibo±MYpqMCgrZ]CoagiMoV XipqM]bdVo@L?^YsYM³
GIHKg\^`u_`H sYbXi]uXiXib^`a Xrp=MC]bcdVWbaK_¥pKg\MC]bXiMV¥Z\HKM auoZiKg\M ^`d o`a MYp=MgiZ^`pKbaKb^`a bXMXiXiMa{Zibo50´K^`gObaqX[Z+oau]M`
Xi^`L?MtoYZ\HK^`g+XIHuo7Mau^Zib]MsZiHuoZ ZiHKMtMWp=MgiZ\X ZiMaqs1Z\^_`b`Mto@L?MCsYboa0"oKMoZiHu^`K_7H1Z\HKMVKausYMCg\XrZ\o`a7Z
te
o7X o?L@Moa ²TK]+HKbMCgiMCa¤KYmo`aKaK^"V1o`ausfgi^Y]Co`]]bo?zy7yK³GIHKMXipqM]bq]oZib^`a0]o`a=Mtg\MbaYd^`g+]Ms1WVXi^`L?M
^7pqMCa "{KMX[Z\b^7auX o`X
7I¢ HKMa0Z\HKMto_`M'^`d o@_`g\^`up1^d¡]^7L?pq^7aKMa{Z\XIg\MCo7]+HKMCX
te
K Hub]+HpKg\^`p=^`giZib^`a
1−αbX X[Z\bba0uXrM
zKI¯[XIZiHKMt"o`KM
te
o?L?MCoa^d puo7X[Z M7Ma{Z\XCWZ\o`WbaK_?ba{Zi^o`]C]^`ua7Z M{Z\giMCL?M"o`KMXI^`gIaK^`Z
uI¯[XIZiHKMt"o`KM
te
ZiHKM'deo`bKg\M'ZibL?Mt HKb]+HHuo7XIqMCMa0^`uXiMg\`MsZ\HKMtL?^7XrZ#dg\M-"{KMCa{ZiV1ba1Z\HKMtpuo`XrZ
GIHKMCa]^`ausYbZib^`aqoV0Zi^ZiHKM ]+Hu^`b]M@^d
a±Z\HKM ]+HK^`b]M@^d
b bX_`b`MCa¤ba}Z\HKM@d^`^" baK_pKg\^`p=^7XibcZ\b^7a¥dg\^`L Z\HKM
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M
t¨% 1"® 1¬¬)«
@`9«
te∈IR+∗ a >0 * α∈]0,1]7 1"«
b1(a, β) =
(1−α)−1/a−1−1
tβe, b2(a, β) =
Γ(a)
Γ(1 + 1/β)Γ(a−1/β) β
tβe, b3(a, β) = aβ+ 1
β−1 tβe.
1"«
Bi i= 1,2,3«)#¨ ¬)%$./=©¨21©+ 16®ª®c¨ >7 1"©I"®ª® % 1"¨%$81
π(β)+¬)% «u"«q¬/&/
(π(β))⊂ [βl, βr]
(i) P(T ≤te|B1) = α, (ii) [T|B2] = te
¨
a > βl−1 (iii) d[T|B3] = te
¨
βl>17
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M ¨ª« )+¨ª« ! 7
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~^`Zib]M'Z\Huo"ZoaMYp=MgiZ]oa_`b`ML?^`g\MZ\Huoa0^7aKMXip=MC]bq]Co"Zib^`a´K^`gIbauXrZ\oaq]M`YHuM]oa_`b`Mto5%© $¨¨ª®¨ª«
¨ q«©§®
[te1, te2] oaus pugi^7uoKbbcZ\bMX
(α1, α2) Xiu]+H ZiHuoZ P(T ≤ tei) = αi
d^`g
i = 1,2 ¢£M}pKg\^`p=^7XiM Z\^¸giMsYu]Mo`a{V}MYpqMCgrZ^7pKbaKb^7a}Z\^ rsKbX\]g\MZ\M ?Xip=MC]bq]Co"Zib^`aqX
i = 1, . . . , P ZiHKMCa¤Z\^¥XrMCM]Z]^`KpKMCX
(ai, bi)
´EbauoV7YMXiKL o`Xrp=MC]bq]Co"Z\b^7auXZiHKg\^`K_7H1Z\HKMtpKg\b^7g
µ|β ∼ G
P
X
i=1
P γiai,
P
X
i=1
bi(P γiai, β)
!
²!{³
HKb]+H1bX#ZiHuMp=^7XrZiMCgib^`gI]^7L?baK_dgi^7L Xiu]]MCX\Xrb`M#oV7MCXibo`abaKdMg\Mau]MCX#^`a{bgiZiuo`9X\oL?pKMCXC ¢¤MCb_7H{Z\X
γi >0
²Xru]+HZiHqo"Z
PP
i=1γi = 1³Oo`giMKYMCs ba!duau]Z\b^7a ^`dkZ\HKM0giMCoZib`MZig\uXrZ baZiHKM¥Xip=MC]bq]Co"Zib^`aqX moZiMCg@ba Z\HKM ogiZib]M`o`a£o`pKpKb]Co"Z\b^7a¤ bhMYML?pKbcdV ²eo`aus¤]o`gibdVK³ZiHKbX]+HK^7b]M`?¯;ZbX'g\MbaYd^7g\]MCs¤{V¥ZiHKM ]^`aW`MWbZ[V
pKg\^`p=MgiZibMCX^dEopKpKb]o"Z\b^7auX
β 7→b(a, β)¡lhXrp=MC]bo`V`WbZopKp=MCo`g\Xh^`WWb^7uXrV@ZiHuoZ
b1(a, β) ²ªZ\H{qX#o`aWV?]^`aW`M
XiKL ^`d#XiM`MCg\o`
b1(a, β)³ rL@bL?b]CXOZiHKM?_`MC^`L?MZ\gib]o`=MHqo{b^`g'^`d
β 7→Pa
i=1x˜βiO¯;ZaKMMsKX'Xr^7L@M?#Mb_`H{Z[V ]Co]Ko"Z\b^7auX'²aK^`Z_`b`MaHKMCgiM³huYZ]o`aMo`XibV =MMa0aWKL?Mg\b]oV1]+HKMC]+7MCs±
¯°aaKMWZ u_7KgiMX#MhsYbXrpuoV'Xr^7L?MhsYMaqXrbZibMCX
m(t)^`d{Z\HKMhpugib^`gL?o`gi_7baqo`sYbXrZig\bKKZib^`a
M HKMCgiM
te= 100 [βl, βr] = [1.1,5] (p, q) = (1.5,1.5) oaqs a= 2¡´Eb_7Kg\M?XiHK^"X
m(t) HuMa te
bXIXru]C]MXiXib7MV]^`aqXrbsYMg\MCs
o7X1Z\HKM£pKgib^`g0L?MCsKbo`a#L?MCo`a#L?^YsYM7*´b_`ugiM z!XiHK^"X1ZiHKM M7^`YZib^`a ^d
m(t) HKMCa te
bXZ\HKM
α ^`g+sYMg
p=Mg+]MCa7Z\bM``d^`ghXiM7Mg+oW"oKMCX^d
α¡GIHKM]^`g\giMCoZib^`a@qMZ[MCMa?puo`g\o`L@MZiMCg\X bausYu]MCs@WVZ\HKM pKg\b^7gL?^YsYMbaK_
bX#giMC`MCo`MsWV?ZiHKM % 1 q§( Y¬Y®ª®7^`dZiHuMpugib^`gIXio`L?pKbaK_$Yba0´Eb_7KgiM K {|%$ ^dpugib^`gIXrbLuoZiMCs
(η, β)"o`KMX o`giM qXrMs d^`g@sYMbL?bZibaK_¥Z\HKM0]^`aW7M¤HWK5¤GIHKM1d^`g\L ^`d ZiHKM]^7gig\Mo"Z\b^7a£g\MLo`bauXaKMCo`gZ\HKM d^7giL ^d Z\HKM
Z\HKM^7giMZib]ouj[^`ba{Z]^7a!qsYMCau]MOog\MCoXiHK^"Ms0WV¢£!²z`y`y{z`³%$=ZiHuMba{7Mg+XrMsKbXrZig\buYZib^`a¥^`dpuog+oL?MZiMgo`uMCX
HKb]+H!bX?uXiuoV pqMCg\]Mb`MCs bX]^`HKMCgiMCa7Z@ bcZ\H!Z\HKM¸]o`X\Xrb]o`=MHqo{b^`g@^ddgiM"7uMa{ZibX[ZMX[Z\bLo"Z\b^7auX@^dZ\HKM
puo`g\o`L?MZiMCg\X'²euXrbaK_?KaKWaK^" a0sKoZ\o7³(¡bcd
β bXI^"7Mg\MCXrZibLo"ZiMsZ\HKMa
η bXIKausYMCgiMX[Z\bLoZiMCsuoaus]^7aW`Mg+XiMV`
¨e ¨¬Y®ª® 9"®¨ 1"©¨ "¬«5©¨e"®©®¨e¨ª®c¨ª«
t
m(t)
0 50 100 150 200 250 300
mean mode median
te=100
´Eb_`Kg\M(MCauXibcZ\bMX
m(t) ^`dEZ\HKMpKg\b^`gLog\_`bauo`
sYbXrZig\bKKZib^`a
M ²bausYMYMCsO{VZiHKMXipqM]bq]oZib^`aO^d
te= 100³
t
m(t)
x
m(x)
x
m(x)
0 50 100 150 200 250
te=100
10%
25%
33%
50%
66%
75%
90%
´b_`ugiMz( kMauXibZibMCX
m(t) ^d ZiHKMpKgib^`gL?o`gi_7baqo
sYbXrZig\bKYZib^`a
M²ebaqsYMYMCsOWVtZiHuMXrp=MC]bq]Co"Z\b^7a^d
α³
eta
beta
0 20 40 60 80 100
020406080100120140
´Eb_7KgiM @(N^`aW`M H{u^`dEo@pKg\b^7gXio`L?pKbaK_@^d puog+oL?MZiMg+X
(η, β)
E #/ '
TW^7L?MoYZ\HK^`g+Xo`XTWbau_`pKKg\IooIoaqsTW^`aK_²r6 `x7³qKubstpKg\b^7g±L?^WsKMbaK_7X bcZ\HtaWKL?Mg\^`uX±HWVWp=Mg\puog+oL?MZ\Mg+X
HKb]+Ho^"}Z\^L?^WsKbcdVkZiHKMMYp=MgiZbaKd^`g\L?oZib^`a'bat^Y]oZib^`ao`aus'Kau]MgiZ\oba{Z[V`
4
XmbausKMCVo`ausTWbaK_`pKugiIoo
²r6 7x7³aK^Z\b]MCs±±bZtHuo`X=MMa£^`qXrMCgi7MCs0Z\Huo"Z'MYp=MgiZ\XkZiMCaus¥Z\^0pKgi^YsYq]M [^Y]o"Z\b^7a}oaqs}X\]oM@Kbo7X t¯°a¤ZiHKbX
#^`g\9^`ug^`pubaKb^`a bXtZ\Huo"ZOZiHKMdu#MYp=MgiZWaK^" MsY_`MbX_7b7Ma£ZiHugi^7K_`H
te
²eo`aus
α bcd te
bXo¸p=Mg+]MCa{ZibM
"oKM³¡~^@^`Yj[M]Z\b7Mk]g\bZiMg\b^`a1o`^"XZ\HKM'#oV7MCXibo`a oauo`VYXrZhZ\^OL?^YsYbdVZiHKbX#MYp=MgiZ#WaK^" MCsY_7M` GIHKM^`aKV
p=^7X\XrbKbbZ[V bX#Zi^?L?^YsYKo"ZiMZ\HKMtMYp=MgiZIuau]MCgrZ+oba7Z[V ZiHKg\^`K_7H Z\HKM]+HK^`b]M^d
aE¯°a0^7Kg XrMCauXrM7WZiHKg\MMtXrZiMCpuXI^d ]CobKg+o"Z\b^7aXiHK^`usqM]^`auXibsYMg\MCs±
7 4 ¬Y®«-%+"®c¨©i«¨21> X[Z\Mp $Yo7]]^7g\sKbaK_Zi^OZiHKMaWKL=Mg oaqs?ZiHKM'auoZiKg\M^`dXipqM]bq]oZib^`auXC7#MpKgi^7pq^{XrM
Xr^7L@M@sYMdeo`KZk"oKMCXd^`g
aGIHKbXkbXsY^7aKMba
§ !q7#MCXibsKMCXCq HKMCa
aHqo`XkqMCMa}]+HK^{XrMCau#Mpugi^7pq^{XrM