HAL Id: inria-00077906
https://hal.inria.fr/inria-00077906v2
Submitted on 6 Jun 2006
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Equivariant HPD credible sets and MAP estimators
Pierre Druilhet, Jean-Michel Marin
To cite this version:
Pierre Druilhet, Jean-Michel Marin. Equivariant HPD credible sets and MAP estimators. Bayesian Analysis, International Society for Bayesian Analysis, 2007, 2 (4), pp.681-692. �inria-00077906v2�
a p p o r t
d e r e c h e r c h e
ISSN0249-6399ISRNINRIA/RR--5923--FR+ENG
Thème COG
INSTITUT NATIONAL DE RECHERCHE EN INFORMATIQUE ET EN AUTOMATIQUE
Equivariant HPD credible sets and MAP estimators
Pierre Druilhet — Jean-Michel Marin
N° 5921
Juin 2006
Unité de recherche INRIA Futurs Parc Club Orsay Université, ZAC des Vignes, 4, rue Jacques Monod, 91893 ORSAY Cedex (France)
Téléphone : +33 1 72 92 59 00 — Télécopie : +33 1 60 19 66 08
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MAP(θ) = τ2
τ2+σ2x+ σ2 τ2+σ2µ .
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MAP(α) =e
τ2
τ2 +σ2x+τ2 +σ2σ2 µ−qτ2σ2
τ2 +σ2 6=eMAP(θ).
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bnRUW = q±lziadW:}gijbdRUW}UgiVkjJzObdkxjUhVW:zCacUrnW
ν®lk@ªWCª MAPν(θ) = Argmax
θ∈Θ
πν(θ|x) = Argmax
θ∈Θ
πλ(θ|x) g(θ)
. #u 1%
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MAP = MAPλ
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{θ:πλ(θ|x)> kγ} ⊂HPDγ(θ)⊂ {θ:πλ(θ|x)≥kγ} ztjl}
Πx({θ:πλ(θ|x)> kγ})≤γ≤Πx({θ:πλ(θ|x)≥kγ}).
Í&ÍÏ67891:
¬Ìo Πx({θ:πλ(θ|x) =kα}) = 0 #µbdRUk¦afk¦afjlgtbbdRlW(e!zCacW2oµgCrfW¤UztV{UwxWko bdRUW{|gCacbdW:rdkxgirf}Ukxacbdrnkl`bdkxgij k¦aSUjUkoµgirnV gCrSkxa |zObgijadgiVW2kj9bdW:rd§Oziwxa4%®`¯%WackxV{Uw_¯rdkbdW.-
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MAP(θ) = \
0<γ<1
HPDγ(θ). # .%
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X|θ∼ B(θ)ztjl} θ∼ U]0,1[
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θ k¦a HPD(θ) =
θ:θx(1−θ)1−x≥kγ .
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α= log(θ/(1−θ)) = logit(θ)® HPD(α) =
α: e(x+1)α (1 +eα)3 ≥kγ0
.
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HPDν(θ)®l9_
HPDν(θ) ={θ:πν(θ|x)≥kγ}. # %
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HPD(θ) = HPDλ(θ)ª fgibdWbdRlztb
HPDν
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γ ¯kbdR
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ν(C) =R
C dν(θ)ª
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f(x|θ)
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}UW!jladkmbu_
|I(θ)|12 ¯ªr;ªb;ª λª º£W}`W:jUgtbnWvH_
JMAP(θ) = MAPJθ(θ)bdRUW = q gi`bztkxjUW:}H_°bnzi¨HkjUh bnRUWvCWÅÀrdW:_`a VW:ziadUrnWziaF}`gCVkjlztbdkxjUhVW:zCaclrdWCª/]HkxVkw¦ztrnw_C®i¯%Wv}`W:jUgtbnW9_
JHPD(θ) = HPDJθ(θ)
bnRUWfq³rnW!hikxgij¯kmbnRbdRUWCWÅÀrdW:_`a³VW;ziadUrdWzCa}`giVkxjlzObnkjUhVW:zCaclrdWCª/º£W2Rlz¥§iW.-
JMAP(θ) = Argmax
θ∈Θ
f(x|θ)|I(θ)|−12 πλ(θ), #@ %
zijl}
JHPD(θ) ={θ : f(x|θ)|I(θ)|−12 πλ(θ)≥kγ}. #p.%
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¸
qaSk¦a³bdRlztb%bnRUW!_wxW:zC}bngW;©9Uk§Ozirdk¦ztj9b³kxj`oµW:rc·
W:jleW2UjJ}`W!r}`kÅ|W:rdW:j9bdk¦ztUwxW2rdW:{lztrztVWbnrdkx¢:ztbdkxgij«ª/ygiJadadW:ziztjJ}yfgi|W!rdb #@ti9%³UrnkW l_egCjladkx}`W:r%z
adkxV°kxw¦ztr2kx}UW:z²kxj£z}`k¦anelanackxgij»gijz{lzt{|W!rgio
Ä
W!rnjlzirn}`g #7ii9%ªX³gijJack¦}`W!r2jUgO¯ z²}`kmÅÀW!rnW!j9bnkxziUwW
rnW!{JztrztVWbnrdkx¢:ztbdkxgij
α=h(θ)®lbdRUW({Jg9aubnW!rnkgCrS}UW!jladkmbu_gto
α¯ªr:ªb:ª bngbdRUWCWÅÀrnW!_`aSVW:ziadUrnW~oµgir
α®
}UW!jUgibdW:}H_
Jα
®Uk¦a(-
πJα(α|x) = πλ h−1(α)|x dαd h−1(α)
|I(h−1(α))|−12
dαd h−1(α)
=πJθ h−1(α)|x
. # %
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/lrdgCV©|ª5# %®i¯%WSgi`bztkxj°bdRUWSoµUjJebdkxgijJztwUW;©Clk§Oztrnk¦ztjle!W%{lrdgC{JW:rcbnkW;agtolbnRUWv = q¡zijl}bdRUWf9fq -
JMAP(h(θ)) = Argmax
α∈h(Θ)
πJα(α|x)
= Argmax
α∈h(Θ)
πJθ h−1(α)|x
= h(JMAP(θ)). # %
zijl}
JHPD(α) = {α:πJα(α|x)≥kγ}
=
α:πJθ h−1(α)|x
≥kγ
= h(JHPD(θ)). #p %
¹ WblaegCjlack¦}`W:r2bdRUWjlgirnVziw W¤UztV{UwxWgtofadW:ebdkxgij t®
X|θ ∼ N(θ, σ2) zijl} θ ∼ N(µ, τ2)ªº»W
RJz¥§iW
I(θ)∝1 ztjl} JMAP(θ) = MAPλ(θ)ª /Ugir α= exp(θ)®$¯%We!zij£}`W:rdkx§iW
JMAP(α) oµrngiV JMAP(θ)H_
JMAP(α) =eJMAP(θ).
X³gCjladkx}`W:r2jUgO¯bnRUW Ä W!rnjUgiUwxwxk W¤UztV{UwxWgtof]HW:ebdkxgij i®
X|θ ∼ B(1, θ) zijl} θ ∼ U]0,1[ªº£WRlz¥§CW
I(θ) = 1/(θ(1−θ)) zijl}
JHPD(θ) =n
θ:θx+1/2(1−θ)1−x+1/2≥kγ
o.
/lgir
α=h(θ) = log(θ/(1−θ))®U¯%WRlz¥§CW
JHPD(α) =
α: exp((x+ 1/2)α) (1 + exp(α))2 ≥kγ
= h(JHPD(θ)).
//kxhiUrnW:a v{UrnW:adW!j9bna$bdRUW{|gCacbdW:rdkxgir}`W:jlackbdkxW:a/gio
θztjl} α¯ªr;ªb;ª«bnRUWiW!Å|rnW!_`a}`giVkxjlzObnkjlhVW:zCaclrdW;a!ª X³gCj9bdrztrn_bngbdRUW
¹
W!|W:adhiUW}`gCVkjlztbdkxjUhVW:ziadUrnW:aSe!zCacWC®`¯³W2gC`bnzikjbu¯³gi·Ìadk¦}`W:}rdW:hikxgijla:ª
QSRUWSgibdRUW:r/Vgibdkx§¥ztbdkxgij(oµgir/bdRUWeRUgCkxe!Wgio
Jθ
zia}`gCVkjlztbdkxjUh~V°W;ziadUrnWk¦a/bdRlztb&bnRUWiW!Å|rnW!_`a/VW:zO·
adUrnW(k¦a2ze!wxzCadadkxe:ztw/jUgijU·@kxj`oµgirnVzObnk§CW({UrnkgCrvoµgCr
θ #pCWÅÀrnW!_`a® ;iU zCadaSztjJ}ºzianadW!rnVzijÀ® :iC%ª yfW:e!ziww$bdRlztb:®À{UrngO§Hkx}`kxjUhbnRUW!rnWzirdWjlgjHUkxanztjJeW{lzirnziVWbdW:rna:® Ä W:rdjlzirn}Ug #c : O %vacRUgO¯%W:}bnRlzObbdRUW
CWÅÀrnW!_`aF{UrnkxgirS}`kxacbdrnkxU`bdkxgijV°kxjUkxVk¢:W:a³bdRUW2ziad_HV{`bdgibdk¦efW¤`{|W:ebdW:}2UwwxlzCe¨C· ¹ W:klwW:r³}`k¦aubztjle!Wv|W·
bu¯%W!W:j²bdRUW({Urdkxgirztjl}bnRUW({|gCacbdW:rdkxgirf}`k¦acbdrnkUUbdkxgijla:ª+vadkjlhgiUrzt{U{UrngCzCeR«®Uko jUg{UrnkgCrf¨HjUgO¯wxW:}`hCW
k¦a(z¥§Ozikw¦ztUwxWgij
θ ztjl}¡kof¯%Wzie:eW!{UbbdRUWiW!Å|rnW!_`aVW;ziadUrdWziajUgCjUkxj`oµgirnVzObdkx§iW{Urdkxgir;®&bdRUW:j¡bdRUW
= q k¦aW;©CJztw.bngbdRUW2oµrnW:©9UW:jCbnkxacb =¹ ¯RlztbdW:§iW!rSbnRUW{lzirnziVWbdrnkx¢:zObnkgCjk¦a!®l{UrdgO§Hk¦}`W:}bdRlW3/&k¦adRUW!r
kxj`oµgCrdVzObnkgCjk¦av}UW'ljUW;}.ª girnW!gO§iW:r:®Hkxj²bdRUk¦ave:ziadWi®l9fq³ae!ztjbnRUW!j²|WbdRUgCUhiR9bvzCafernW:}`kxUwxWacW!bna
ztrngiUjJ} bdRUW =¹ ®J¯RUW:rdW(bdRUWbdW:rdV zirdgCUjl}²Vz¥_²JW°ztUladkx§iW(kxj¸e:ziadW(gtoFVUwbdkxV°g`}Uziw&{|gCacbdW:rdkxgir
}Ukxacbdrnkl`bdkxgij #µVUwmbnkVg`}Uziw«kxav}`W'ljlW:}¯ªr;ªb:ª/bdRUWCWÅÀrnW!_`aSVW:ziadUrnW1%ª
ʵÇ/Í«Ê É
0.0 0.2 0.4 0.6 0.8 1.0
0.000.050.100.150.200.250.30
θ
−10 −5 0 5 10
0.000.050.100.150.200.250.30
α
/&kxhilrdW- qgCacbdW!rnkxgir}`W!jJackbdkxW:aSgio
θ ztjJ} α¯ªr:ªb:ªbnRUWCWÅÀrdW:_HaSVW;ziadUrdW~¯RUW:j
x= 0
),3 !"' °"& % / (01%/S
¬j»bdRlkxaadW:ebdkxgij«®$¯³W}`k¦ade!lana~adW!§CW!rztwVWbnRUg`}Ua~bdg}`W:rdkx§iWztj£W:©9Ukx§OztwxW!j9bgtoS = qaztjJ}»9fq~a
¯RlW!jjHUk¦adzijleWf{JztrztVWbnW!rFztrnWf{UrnW:adW!j9bFkxjbdRlWvVg`}`W!w@ªº»WvzCadadUVWbnRlzObFbnRUWv{JztrztVWbnW!r
θk¦a³ad{Uwxkmb kxj9bdgbu¯³g{lztrdbna -
θ= (θ1, θ2)∈Θ1⊗Θ2
¯RUW!rnW
θ1
kxabdRlW{lzirnziVWbdW:rvgiokj9bnW!rnW:acb~ztjJ}
θ2
k¦abdRUW
jHUk¦anztjle!Wiª²º»W}`W!jlgtbdW9_
πν(θ1|x) bdRUW}`W!jJackbu_»giobdRUWVzirdhCkjJztwF{|gCacbdW:rdkxgir(}Ukxacbdrnkl`bdkxgij¡gio
θ1
¯ªr;ªb;ªbdRUWVW:zCaclrdW
νªFQSRUWe!girnrdW;ac{|gijl}UkjUh = q
ν
ztjl}²fq³
ν
zirdW
MAPν(θ1) = Argmax
θ1∈Θ1
πν(θ1|x) #c :.%
ztjJ}
HPDν(θ1) ={θ1:πν(θ1|x)≥kγ} #c i 1%
Ä W;e!ztJacW~bdRlWiW!Å|rnW!_`a{Urnkxgirf}`gHW:afjUgtbv}`k¦acbdkxjUhiUk¦adR|Wbu¯%W!W:j²{lztrztVWbnW!rgio/kxj9bdW!rnW:acbvztjJ}jHUk¦anztjle!W
{JztrztVWbnW!r;® Ä W:rdjlzirn}Ug #u ; O%({Urngi{|gCadWz»jUW!¯'zi{U{UrngCzieR¶e:ztwxwW;}¡rnWoµW!rnW!jJeW{lrdkxgirzt{U{lrdg9zieR«ª»¬j
bnRUk¦aS]`W:ebnkgCj«®H¯³W2adRUgO¯±RUgO¯±¯%W~e:ztjladW:}bdRUk¦aSrnWoµW!rnW!jJeWv{lrdkxgir%ziaS}`giVkxjlzObnkjlh(VW:zCacUrnWfbng°}UW'ljUW
W;©9Uk§Ozirdk¦ztj9b = qa2ztjl}=vq~a!®.e!ziwwxW:}=9_²ztjJztwxgihi_¯kmbnR£]HW;ebnkgCj¸`®À = qa2ztjl}9fq³a:ª~Q&¯%g
e:ziadW:azirdW»egijJack¦}`W!rnW:} -=bdRlW»e!zCacW¸¯RUW!rnWbdRlW!rnW=kxaegCjl}`kbdkxgijlziwadU`suW;ebdkx§iW¸kj`oµgCrdVztbdkxgij oµgirbdRUW
jHUk¦anztjle!W~{JztrztVWbnW!rztjl}bdRlWe!ziadW2¯RUW!rnW~bdRUW:rdW2k¦aSjUgijlWiª
! "$#%&' "$(*),+%-. /-01(23(*)(4%)
]`U{U{|gCadW=bdRJzObz adU`suW:ebdkx§iW¸e!gijl}UkmbnkgCjlztw~{UrnkgCrk¦az¥§Oztkxw¦ztUwxWoµgir
θ2
hCk§CW!j
θ1
ª º£W£}`W:jUgtbnW¸H_
πλ(θ2|θ1) kmba°}UW!jladkmbu_¯ªr:ªb:ª
몣¬j¶bdRUk¦ae!ziadWi®F]Hlj²zijl} Ä W!rnhiW!r#u :C %({Urngi{|gCadWbu¯³g£}`kÅ|W:rdW:jCb zi{U{UrngCzCeRUW:avbdg=}`W:rdkx§iW°rnWoµW!rnW!jJeW{UrnkgCrnaoµgir
θ1
ªº»WVkxVkxe°bnRUW!kxr(zt{l{Urdg9zieRUW;azijl}»bdRUW:rdWk¦a2bu¯%g
rnW:zCacgCjlztlwWgi{`bnkgCjla%oµgir 'ljJ}`kjlhz°}UgiVkjJzObdkxjUhVW:zCacUrnW2gij
Θ1
ª
56 87:9;egCjladkx}`W:rfbnRUWVzirdhCkjlziw$Vg`}`W!w
f(x|θ1) =R
f(x|θ1, θ2)πλ(θ2|θ1)dθ2
ªvW:jUgtbnW(H_
Im(θ1)bnRUW//kxadRUW!r$kj`oµgCrdVztbdkxgij2VzObdrnk¤voµgir
θ1
gC`bnzikjlW:}oµrdgCVbnRUWFVztrnhikxjlztwOVg`}`W:w7ª }`giVkxjlzObnkjUh
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VW;ziadUrdWSe!zij|WSbdRlWSCWÅÀrnW!_`aVW:ziadUrnW³gCj
Θ1
¯kbdR}`W:jlackbu_¯ªr:ªb:ª
λ{Urngi{|girdbdkxgijJztw9bdg
|Im(θ1)|1/2ª
¬jbnRUkxae:ziadWi®HbnRUW ¸ q±ztjl}bnRUWCvqzirdW}`W('ljUW:}H_
JMAP1(θ1) = Argmax
θ1∈Θ1
πλ(θ1|x)
|Im(θ1)|1/2
,
JHPD1(θ1) =
θ1: πλ(θ1|x)
|Im(θ1)|1/2 ≥kγ
. JMAP1
zijl}
JHPD1
zirdWgiH§HkgClacwx_vW;©9Uk§Ozirdk¦ztj9b«oµgCr&z
1−1acVgHgtbnRrdW:{lztrztVW!bdrnk¢;zObdkxgij~gij2bnRUW%{lzO·
rztVW!bdW!r.gio9kxj9bdW:rdW;aub;ª +fjUoµgirdbdUjlztbdW:w_C®!bnRUW //kxadRUW:r.kj`oµgCrdVztbdkxgij2VzObdrnk¤voµgir
Rf(x|θ1, θ2)πλ(θ2|θ1)dθ2
k¦aSgto bnW!j}`keUwbbdge!giV{U`bnWiªFQSRUk¦a}`ke!Uwbu_Vgtbnk§OzObnW:a%bnRUWkj9bnrdg`}`lebdkxgijgto ztjUgibdRUW:rgi{`bnkgCj«ª
56 87 ; /lgiwxwgO¯kxjUh Ä W!rnjlztr}`g #u ; O.%®(]HUjzijl} Ä W:rdhCW!r)#c :i%²{Urngi{|gCadW£bdg±VzO¤`kxV°kx¢!W
zCac_HV{`bngtbdk¦e!ziwwx_¶bnRUW¸W!¤`{JW;ebdW;} 2UwxwlzCe¨9·¹ W!kxUwW:r}`kx§iW:rdhCW!jle!WJW!bu¯³W:W!j bdRlW¸Vztrnhikxjlztw{|gCacbdW:rdkxgir
gio θ1
zijl}bdRUW(VzirdhCkjJztw.{UrnkgCrgto
θ1
ªSQSRUkxafwW;zi}UaSbngbdRUW}`kxacbdrnkxU`bdkxgij²gCj
Θ1
¯kmbnR=}`W!jladkbu_¯ªr:ªb:ª
λ{UrdgC{JgCrcbnkgCjlztw|bng
exp 1
2 Z
πλ(θ2|θ1) log
|I(θ1, θ2)|
|Ic(θ2|θ1)|
dθ2
¯RlW!rnW
I(θ1, θ2) k¦abnRUW /&k¦adRUW!rkj`oµgCrdVztbdkxgij¶VzObnrdk¤lziadW:}gCj
f(x|θ1, θ2) ztjl} Ic(θ2|θ1) kxa(bdRUW
//k¦acRlW!rSkjUoµgirnVztbdkxgijVztbdrnkm¤JziadW:}gCjbnRUW2VgH}UW!w
f(x|θ1, θ2)¯RUW:rdW θ1
k¦aS¨HjUgO¯j«ª QSRUk¦a%kxaSW;adadW!j`·
bnkxziwwx_²bdRlWadgiwx`bnkgCj¸ladW:}¸kj Ä W!rnhiW!rSztjJ} Ä W:rdjlzirn}Ug$#u ; iH® ;i9%®«UUb2RlW!rnW°zacl`suW:ebdkx§iWegijJ}`km·
bnkgCjlztwÀ{Urnkxgir%oµgir%bdRlW~jHUk¦anztjle!W{lzirnziVWbdW:r³hCk§CW!jbdRUW2{lzirnziV°W!bdW:r%gio$kxjCbnW!rnW:acbkxa%ladW:}.ª º£W2{Urngi{|gCadW
bngJacW~bdRlW~{lrdW:§9kxgiJa%}Ukxacbdrnkl`bdkxgij²ziaS}`gCV°kxjlztbdkxjUhVW;ziadUrdW~gij
Θ1
ª¬jbdRUk¦ae!zCacWC®HbdRUW
=
q ztjJ}
bnRUW9fqzirdW}`W('ljUW;}H_
JMAP2(θ1) = Argmax
θ1∈Θ1
πλ(θ1|x) expn
1 2
Rπλ(θ2|θ1) log|I(θ
1,θ2)|
|Ic(θ2|θ1)|
dθ2
o
,
JHPD2(θ1) =
θ1: πλ(θ1|x) expn
1 2
R πλ(θ2|θ1) log
|I(θ1,θ2)|
|Ic(θ2|θ1)|
dθ2
o ≥kγ
. JMAP2
ztjJ}
JHPD2
ztrnW~gCH§9kxgiJacwx_W:©9Ukx§Oztrnkxzij9b%oµgCrvz
1−1 acVgHgtbnRrnW!{JztrztVWbnrdkx¢:ztbdkxgijgCjbdRUW {JztrztVWbnW!rSgto/kj9bdW:rdW;aub;ª
¹ Wbla³egCjlack¦}`W:rFzadziV°{lwW
X1, . . . , Xn
oµrngiV z2jlgirnVziwl}`k¦aubnrdkxU`bnkgCj¯kmbnRW¤`{|W:ebzObnkgCj
θ2=µ
zijl}¶acbnzijl}Uztr}¶}`W:§Hkxztbdkxgij
θ1 = σ® bdRlW{lzirnziVWbdW:rgiofkj9bnW!rnW:acb:ª¶]HU{U{|gCadWbdRlztbbnRUWe!gijl}UkmbnkgCjlztw {lrdkxgir}`k¦acbdrnkUUbdkxgij£oµgir
µ hikx§iW:j σ k¦ajUgirnVztw ¯kbdR¡W!¤H{|W:ebnztbdkxgij
m ztjJ}»§Ozirdk¦ztjle!W
τ2ª {U{Uwx_HkjUh {lrdgC{Jg9ackbdkxgij ¸gto]Hlj²zijl} Ä W!rnhiW!r #u ;i %®%Y{`bnkgCj }UgiVkjJzObdkxjUh»V°W;ziadUrnWRlzia°}`W:jlackbu_¡¯ªr:ªb:ª
λ {Urngi{|girdbdkxgijJztw bng
1
σ2 + σ2
(n−1)(σ2+nτ2)2 1/2
®Fzijl} Y{`bnkgCj =}UgiVkjJzObdkxjUh=VW;ziadUrdWRlzia
}UW!jladkmbu_~¯ªr:ªb:ª
λ{lrdgC{JgCrcbnkgCjlztwObng
1/σª&QSRUW;acW bu¯%gv}`gCVkjlztbdkxjUhvVW;ziadUrdW;a«ztrnW}`kÅÀW!rnW!j9b:ª/fgO¯%W!§iW:r:®
¯RlW!j
n→ ∞®`bdRlWacW;egijJ}}`W:jladkmbu_e!gijH§iW:rdhCWljUkmoµgCrdVwx_bdg°bnRUW 'lraubfgCjUWiª
ʵÇ/Í«Ê É
¹ WbJa(jUgO¯ e!gijladkx}UW!rbnRUWUkx§OztrnkxztbdWlkjUgCVkxziw³Vg`}`W!w³{Urngi{|gCadW:}H_¡X³rngO¯f}`W:rSzijl}²]H¯³W:WbnkjUh
#c :i%SztjJ}rnW!§Hk¦ackbdW;}H_qgCwxadgijztjl}ºzianacW:rdVztj #u ;ii%-
f(x1, x2|θ1, θ2) = m
x1
θx11(1−θ1)m−x1 x1
x2
θx22(1−θ2)x1−x2 I1,...,m(x1)I1,...,x1(x2).
¯RlW!rnW
IA
k¦aSbnRUWkxjl}`k¦e!zObngirSoµUjJebdkxgijgCj
Aztjl} mk¦afacl{U{Jg9acW;}bdg|W¨HjUgO¯j«ª³]Hl{U{Jg9acW2bnRlzObvbdRUW e!gijl}UkmbnkgCjlztw }`k¦aubnrdkxU`bnkgCj¸gio
θ2
hikx§iW!j
θ1
k¦az Ä W!bnz}`kxacbdrnkxU`bdkxgij£¯kbdR£{lztrztVWbnW!r
a ztjl} bª /lgir
adleR²z°V°g`}`W:w7®
|I(θ1, θ2)|= (1−θ1)−1θ2−1(1−θ2)−1 ztjJ} |Ic(θ2|θ1)|=θ1(θ2(1−θ2))−1ª ¬Ìbfkxa
§CW!rn_W:ziad_bdgadRUgO¯±bdRJzObY{`bdkxgij» ~zijl}Y{`bdkxgij²(}`gCVkjlztbdkxjUh°V°W;ziadUrnW:a%ztrnWvbnRUWadziV°W2ztjJ}Rlz¥§CW
}UW!jladkmbu_¯ªr;ªb;ª
λ{Urngi{|girdbdkxgijlziw|bdg
θ−1/21 (1−θ1)−1/2ª
]Hlj²zijl} Ä W!rnhiW!r #c :i%2egCjlack¦}`W:rdW;}=bnRUWe!zCacW°¯RUW!rnW
θ1
ztjl}
θ2
ztrnWkjl}UW!{|W!jl}`W:j9b:ª /lgir2bdRlkxa
gibdRUW:rv{Urnkxgirfkxj`oµgirnVzObnkgCj«®l¯%W(e!zij=ztw¦acgVkxVkxebdRUW:kr~zt{U{UrngCzCeRbng}`W('ljUW(z}`giVkxjlzObnkjUhV°W;ziadUrnW
gCj
Θ1
ª $ ' ! "$#$' "$(4) +$- /- ( 3(* )(4%)
¬Ìojlg adU`suW:ebdkx§iW£egijJ}`kmbnkgCjlztw{UrnkgCroµgir
θ2
hCk§CW!j
θ1
k¦az¥§¥zikw¦ztlwWC®¯³W»{UrdgC{Jg9acW=bdg VkxVkxe¸bdRUW
rnWoµW:rdW:jleWS{Urnkxgir zt{U{lrdg9zieR(gio Ä W:rdhCW!rztjl} Ä W!rnjlztr}`g#u ; iU®U :CC%ªQSRUk¦a wxW:zi}la/bdg2bdRlWf}`giVkxjlzObnkjUh
VW;ziadUrdW~gij
Θ1
¯kbdR}`W!jJackbu_¯ªr:ªb:ª
λ{lrdgC{JgCrcbnkgCjlztw|bdg
exp 1
2 Z
|Ic(θ2|θ1)|1/2log
|I(θ1, θ2)|
|Ic(θ2|θ1)|
dθ2
.
Yvo bnW!j«®|bnRUWkxj9bdW:hirztw
R|Ic(θ2|θ1)|1/2log|I(θ
1,θ2)|
|Ic(θ2|θ1)|
dθ2
kxajUgib~}`W('ljUW:}ǻ~QSRUWegCV{lziebacl{U{JgCrcb
zirdhCUVW!j9bbdRlztbFkxa bu_9{lkxe:ztwxw_JacW;}kxj°bdRUWrnWoµW:rdW:jleWS{UrnkxgirFzt{l{Urdg9zieR #Ä W!rnhiW:rSzijl} Ä W!rnjlztr}`gH®l ;iC%
Vz¥_¸bdRUW:j¡JWzi{U{UwxkW;}RUW!rnWiªX³RUgHgCadWz²jUW:acbdW;}¡acW;©9UW!jle!W
Θ1 ⊂ Θ2 ⊂ . . . gtoegCV{lzieb(acUJacW!bna gio³bnRUW{lzirnziVWbdW:rac{lzCeW
Θ acJeR»bnRlzOb
∪iΘi = Θ ztjJ} |Ic(θ2|θ1)|1/2 RJzia 'ljlkmbnWVziana2gij
Ωi = {θ2; (θ1, θ2)∈Θi}oµgirfztwxw
θ1
ª ¹ Wb
Ki(θ1) =R
Ωi|Ic(θ2|θ1)|1/2dθ2
ztjl}
πi(θ1) = exp 1
2 Z
|Ic(θ2|θ1)|1/2log
|I(θ1, θ2)|
|Ic(θ2|θ1)|
dθ2
.
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i→∞lim
Ki(θ1)πi(θ1) Ki(θ(0)1 )πi(θ1(0))
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Θ1
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=
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¹
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bnRUW = qUjl}`W:rbdRUW ¹ zt{lwxzCeW{UrnkgCroµgCr
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¹ W!|W:adhiUWvV°W;ziadUrnWiª/¬jbdRlztb%e:ziadWi®
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