Individual prediction regions for multivariate ... · better detect abnormal alues.v Recentl,y Wang...
Transcript of Individual prediction regions for multivariate ... · better detect abnormal alues.v Recentl,y Wang...
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HAL Id: hal-00856736https://hal.archives-ouvertes.fr/hal-00856736v3
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Individual prediction regions for multivariatelongitudinal data with small samples
Didier Concordet, Rémi Servien
To cite this version:Didier Concordet, Rémi Servien. Individual prediction regions for multivariate longitudinal data withsmall samples. Biometrics, Wiley, 2014, 70 (3), pp.629-638. hal-00856736v3
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♥ ♣rt♦♥ r♦♥s ♦r ♠trt ♦♥t♥ tt s♠ s♠♣s
❱
❱ ❯♥rsté ♦♦s ❯ ♦①♠sr ♥tr ♥ ♦♦ ♦①♦♦② ♦♦s
r♠sr♥t♦♦s♥rr
strt
♦♦♣ s ♠♦r ♥ ♠♦r s ♥ ♠♥♦♣♥ ♦♥tr♦ t♦ ♥t② ♥♦r♠rsts ♥ ♥ ♥ rr♥t② ♦♦♣s r ♠♦st② rr ♦t r ② r s♥ rr♥ ♥trs tt ♦♥t♥ t s ♦sr ♥ 100(1 − α) ♦t②♥♦♣ ♥s srt♦♥s ♦ t ♦t♦♥ ♦ t rs ♦r t♠♥ s♠♣ ♦ N t②♥♦♣ ♥s ♦s ts rr♥ ♥trs t♦ ♥③ ② t♥ ♥t♦ ♦♥t t ♣♦ss t ♦ ♦rs ♥ s♦♠ ♣r♦s♦srt♦♥s ♦ ts rs ♦t♥ ♥ t ♥ s t②♥♦♣ ♦r r ts ♥③ ♥trs s♦ ♦♥t♥ 100(1 − α) ♦ ♦srs ♦♠♣t t ♣r♦s ♦sr s ♥ ts ♥ ♥r ♠t♦s t♦ ts ♥trs r t t② ♦ ♦♥② r ② r ♦♦♣tr t ♣♦ss ♦rrt♦♥s ♦r t♠ t♥ t♠ ♥ ts rt ♣r♦♣♦s ♥r ♠t♦ t♦ ♦♥t② ♦♦♣ sr ♦rrt rs ♦r t♠ s ♠t♦♦♦② rs ♦♥ ♠trt ♥r ♠① ts ♠♦ ❲ rst ♣r♦ ♠t♦ t♦st♠t t ♠♦s ♣r♠trs ♥ ♥ s②♠♣t♦t r♠♦r N r ♥♦ t♥ r (1−α) ♥③ ♣rt♦♥ r♦♥ ♦♠t♠s t s♠♣ s③ N s♥♦t r ♥♦ ♦r t s②♠♣t♦t r♠♦r t♦ rs♦♥ ♣rt♦♥ r♦♥t s ♦r ts rs♦♥ ♣r♦♣♦s ♥ ♦♠♣r tr r♥t ♣rt♦♥ r♦♥s tts♦ ttr ♦r s♠ N ♥② t ♦ ♠t♦♦♦② s strt ② t♦♦♣ ♦ ♥② ♥s♥② ♥ ts
②♦rs ♦rrt ♦r rt ♦♥t♥ ♦♦♣ trt ♠① ss♥♠♦ P♥ st♠t♦r Prt♦♥ r♦♥ r♥ ♥trs
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♥tr♦t♦♥
♦♥t♥ ♦♦♣ ♦ ♦♦ rs s ♠♦r ♥ ♠♦r s ♥ ♣r♥t ♠♥t ♦♥ssts ♦ ♠♦♥t♦r♥ t ♠rrs ♦ ♠♣♦rt♥t ♥t♦♥s ♦r t r② tt♦♥ ♦ s♦②♣r♦rss sss t s♥ ♣s ♦r ①♠♣ t ♣r♦stt s♣ ♥t♥P s s t♦ tt ♣r♦stt ♥r ♥ ♠♥ s♠ ♥ ♦ ♦♦♣ s s②st♠t②♦♥ t t♥rs s♥ tr t ♥ t t♦ tt t ♥♥♥ ♦ ♦st② ♥s♣♦rt ②♥ ♦r tts ♥t♦♣♥ ♦♥tr♦ t♦rts tr② t♦ ♥r③ t s ♦ ♦♦ ♣ss♣♦rt ♦♥ssts ♦ ♦♥t♥ ♦♦♣ ♦ s♦♠ ♥♦♥♦s sst♥s♦ ♥trst ♥ ♦rr t♦ tt ♥♦r♠ rt♦♥s ♥ ♥ ♥ ♦tts t ❩♦r③♦♥ ♦ss st♥r ♠t♦ ♦ ♦♥ ts ♦♦♣s s t♦ s t s♦ rr♥ ♥trs s ♥trs ♦♥t♥ ① ♣r♥t s② ♦ ♠sr♠♥ts tt ♥ ♦sr ♥ t② ♥s ♦r ts ♠t♦ srs r♦♠ sr s rst t♦s ♥♦t s ♥ ♥♦r♠t♦♥ t② ♥ ♥ ①tr♠ s ♦tst rr♥ ♥tr ♦r s♦♠ ♦tr ♥s s ♥s t rr♥ ♥trr ♣t♦♦ ♦♥ ts ♥trs r t ♥ ♥ ♥rt r♠♦r r② r t♦t t♥ ♥t♦ ♦♥t t ♣♦ss ♦rrt♦♥s t♥ t♠ ♥② t♦s ♥♦t ♦♥t ♦r tr ♦t♦♥ ♦r t♠ t♥ ♥ ♥ ♥ rr♥ ♥trs ♦r ♣rt♦♥ ♥trs ♠tt ts ② ♦♥ t♦♥strt♦♥ ♦ rr♥ ♥ s ♦♥ t ♦sr s ♥ t② ♥♥ t♥ ♥t♦ ♦♥t s♦♠ ♦rs s s s① trtr ♦♥ ts sts ♣♥t ♥ t s ♠t♦♦♦② s t♦ s ♥r♥♦♥♥r ♠① ts ♠♦s ♥ ♥s ❱r ♥ ♦♥rs ♥ ♥ t♥♥ ♥ ts♠♦s t ♦srt♦♥s r s② ss♠ t♦ ♥♣♥♥t ♦♥t♦♥ t♦ t ♥s♣ ♣r♠trs ♦♠♣♦♥ s②♠♠tr② ss♠♣t♦♥ ♦ ♦r ♥♦ t ♦♣♠♥t♦ r ♠t♦s t♦ tt ♥♦r♠ rt♦♥s ♦ ♦♥t♥ rs s r♠♥♠t ♦tts t ♣r♦♣♦s ②s♥ ♣♣r♦ t♦ ♦♠♥ ♣♦♣t♦♥r♠ts ♥ ♥s trs♦s rtss ts ♠t♦ s t ♥ ♥ ♥rtr♠♦r rs ♦♦♣ s s② ♣r♦r♠ ♦♥ sr ♠rrs ② ♦♥sq♥t ♥ rr♥ ♥trs r t ♦♥ ♠rr ♥♣♥♥t② ♥tt♦♥ sststt ♥ r♦♥s s♥ s♠t♥♦s ♥♦r♠t♦♥ ♦♥ ♦rrt rs ♦ ♣ t♦ttr tt ♥♦r♠ s ♥t② ❲♥ ♥ ♥ ♣r♦♣♦s ♠t♦ t♦ ♣rt♦♥ r♦♥s ② s p ♦rr t♦rrss ♣r♦ss t♦ ♠♦ t t♦♦rrt♦♥ ♦ r t t♠ t ♦rrt♦♥s t♥ r♥t rs s ss♠ t♦ ①♦r t♠ s r♦♥s r t s♥ t s②♠♣t♦t strt♦♥ ♦ sttst ♥ ♦tr♦rs t strt♦♥ ♦ t sttsts s ♦♠♣t ss♠♥ tt t ♠♦ ♣r♠trs r♥♦♥ st♠ts r s t♦ ♦♠♣t t ❲ ts ♣♥ ♠t♦ s s② t♦ s tsr② ♥tr ♦s ♥♦t r♥t ♥ ①t ♦r rt ♦r t ♣rt♦♥ r♦♥ s t♦s ♥♦t ♦♥t ♦r t ♠♣rs♦♥ ♦ t ♣r♠tr st♠ts s ♥ r ♣r♦♠♥ t s♠♣ s③ s s♠ r♥♦rs♥ ♥ ♦① ♥ ts s ss♠♥ ttt s②♠♣t♦t r♠♦r ♦s ♦ t♦ ♦♥sr ♣♣r♦①♠t♦♥ rr♦rs r♦rs♣ tt♥t♦♥ s t♦ ♣ t♦ ts ♣r♦♠ t♦ ♦♥tr♦ t r ♦r rt ♦ t t
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♣rt♦♥ r♦♥♥ ts rt ♣r♦♣♦s t♦ ♥ ♥ ♣rt♦♥ r♦♥ r♦♠ ♣r♦s ♦srt♦♥s♦ ts rs rr ♦t ♥ t s♠ ♥ ♥ ♠♦ ♣r♠tr st♠ts ♦srt♦♥s ♦t♥ ♥ ♥ ♥ r ss♠ t♦ ♦rrt ♦r t♠ ♦rrt♦♥t♥ r X1 t t♠ t1 ♥ r X2 t t♠ t2 s ♥♦t ss♠ t♦ qt♦ t ♦rrt♦♥ t♥ X1 t t♠ t2 ♥ X2 t t♠ t1. s s t♦ ② strtrt♦♦rrt♦♥s tt ♥♥♦t rt② st♠t ② ♦♥♥t♦♥ ♠t♦s t ❳♣r♦r ♥ ♦r t ♥♠ ♣ r♦r ♣r♦♣♦s s♣ st♠t♦♥♠t♦ ♠♦ s t♦ ts ♣rt♦♥ r♦♥s s t ♦♥ t♦♥ ♥ t st♠t♦♥♦ ts ♣r♠trs s ♣r♦r♠ ♥ t♦♥ ♣rt♦♥ r♦♥s r t♥ t ♥ t♦♥ s♥ ♣♥ ♣♣r♦ r r♥t ♦rrt♦♥s ♦ t s②♠♣t♦t ♦♥♥ r♦♥r ♣r♦♣♦s ♥ ♦♠♣r ♥ t♦♥ s ♦rrt♦♥s ♠ t ♦rrt♥ t ♣♥st♠t♦♥ ♦ t ♣rt♦♥ r♦♥ rst t♦ ♦♠ r♦♠ t ❯ ♥ ❱♦♥ ♦♥s t t tr s ♥s♣r ② t ♦r ♦r♥ ♥ ♦♥s t r tst ♦♥ ♥② ♥s♥② ♦♦♣ ♥ts s t♥ trt ♥ t♦♥ ♥② sss♦♥ s ♣r♦ ♥ t♦♥
♠♦
t s ♥♦t Xi = [Xi1 : · · · : Xir] t ♠sr♠♥ts ♣r♦r♠ ♥ t ith ♥ ♦ s♠♣ ♦ s③ N t♦rXij ♦♥t♥s t ni ♦srt♦♥s rr ♦t ♦r t♠ ♦r t jth
r ♦r ♣rs② Xijk s t ♦sr ♦r t ith ♥ ♦r t jth rt t♠ tik ❲t♦t ♦ss ♦ ♥rt② ♥ ss♠ tt ti1 ≤ ti2 ≤ . . . ≤ tini
♦t tt t rs r s♣♣♦s t♦ ♠sr t t s♠ t♠ ♦r ♥ ♥ t t♠♠srs ♠② r r♦♠ ♦♥ ♥ t♦ ♥♦tr ❲ ss♠ tt ♣ t♦ ♠♦♥♦t♦♥tr♥s♦r♠t♦♥
Xi = Biβ +TiΦi + ζi
r Bi ♥ Ti r ♥♦♥ r♥ ♦rt ♠trs ♦ ♠♥s♦♥s ni × p ♥ ni × qrs♣t② β = [β1 : · · · : βr] s p×r ♠tr① ♦ ♣r♠trs s t♦ sr t ♣♦♣t♦♥♠♥ Φi = [Φi1 : · · · : Φir] ♥ ζi = [ζi1 : · · · : ζir] r rs♣t② q× r ♥ ni× r ♠trs♦ ♥♦sr ss♥ r♥♦♠ ts r♥ ♦ t ♦♠♣♦♥♥ts ♦ t r♥♦♠♠tr① ζi s ss♠ t♦ ② strtr
cov (ζijk, ζij′k′) = Σjj′ρtik−tik′jj′ k > k′ ♥ cov (ζijk, ζij′k′) = Σjj′ρ
tik′−tikj′j k < k′
r ρjj′ ∈ [0, 1] ♥ Σjj′ = αjj′σjσj′ ♥♠rs αjj = 1, ∀j ∈ 1, . . . , r αjk = αkj ∈[−1, 1] ∀j 6= k ∈ 1, . . . , r ♥ ρjk ∈ [0, 1] ∀j, k ∈ 1, . . . , r σj r♣rs♥ts t st♥rt♦♥ ♦ t jth r t ♠sr♠♥t t♠ ♦rrt♦♥ t♥ ζijk ♥ ζij′k′s ss♠ t♦ ρtik−tik′
jj′ ♦r k > k′ ♥ ρtik′−tikj′j ♦r k < k′ s ♠♥s tt ♦ ♥♦t ss♠
tt t ♦rrt♦♥ t♥ t jth r ♥ ζi ♠sr t t♠ k ♥ t j′th r ♥
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ζi ♠sr t t♠ k′ s t s♠ s t ♦rrt♦♥ t♥ t jth r ♥ ζi ♠srt t♠ k′ ♥ t j′th r ♥ ζi ♠sr t t♠ k ♠♦r r♥ t t♣♣r ♦ ❲♥ ♥ ♥ s tt t② ss♠ tt t ♦srt♦♥ t♠s tik r q②s♣ ♥tr ♥♠rs ♥ tt ♦r j ♥ j′ cov (ζijk, ζij′k′) = Σjj′ρ|t−t′| r ρ|t−t′| st ♦rrt♦♥ ♦ ♥ t♦rrss ♣r♦ss ♦ ♦rr p ♠tr① ♦ t ♦r♥ ♦ t ζi s r♥♦r♥ ♠tr① s t s s②♠♠tr ♥ ♣♦st♥t ♠tr① s t r♦♥r ♥ r ♣r♦ts ♦ t♦ ♣♦sts ♠trst ts ♠♦ rt♥ s s② t♦ ♥rst♥ ts ♠t♠♥s♦♥ ♥tr ♦s♥♦t tt t st♠t♦♥ ♦ ♣r♠trs ♥ t strt♦♥ ♥t♦♥ ♦ Φi ♥ ζi s rrt ts ♠♦ ♥ t♦r r♠♦r t♦ tt rtr st♠t♦♥s t s ♥ψi = vec(Φi) t t♦r ♦t♥ ② st♥ t ♦♠♥s ♦ Φi ♦♠♥s ❲ ss♠ ttψi ∼
iidN(0,Ω) r♥ ♠tr① Ω = [ωjm]jm s ♦♣rtt♦♥ t q × q r♥
♠trs ωjm = cov(Φij,Φim)♠r② t t♥ st rr♦r ζi ♥ st♦r ♦♠♥s ♥t♦ t♦r εi =vec(ζi) ∼ N(0,Λi(ρ,Σ)) ♠tr① Λi(ρ,Σ) ♥ rtt♥ s D
−1i R
−1i D
−1i r
D−1i = diag(σ1, . . . , σ1, σ2, . . . , σ2, σr, . . . , σr) t σj r♣t ni t♠s s t s
ss♠ t♦ ♦♥st♥t ♦r t♠ ♠tr① R−1i (ρ) s ♦♣rtt♦♥ t ni × ni
♠trs ωijk t
ωijk(ρ) = (♦rr (ζijl, ζikf ))l,f∈1,...,ni= αjkρ
|tif−til|
jk
♥ αjj = 1. ♠tr① ωijk(ρ) ♦♥t♥s t ♦rrt♦♥ t♥ t jth ♥ kth r tt r♥t s♠♣♥ t♠s εis r ss♠ ♠t② ♥♣♥♥t ♥ ♥♣♥♥t ♦ t ψis t s ♥Yi = vec(Xi) Ai = 1r ⊗Bi ♥ Zi = 1r ⊗Ti ❯s♥ ts ♥♦tt♦♥s t ♠♦ ♥ rrtt♥ s
Yi = Aiθ + Ziψi + εi
r θ = vec(β) s ♠♦ ♠② ♣♣r t♦ st♥r ♥r ♠① t ♠♦ ♦s♣r♠tr ξ = (θ,Ω,Σ,ρ) ∈ Ξ ♥ s② st♠t s♥ st♥r sttst s♦tr♦r t ♦r♥ ♠trs ♦ ts ♠♦ r ② strtr ♥ tr st♠t♦♥♥s r ♦♣♠♥t s ♦♥ ♥ t♦♥ ss♠ tt nw ♦srt♦♥s ♦ t r rs r t t♠s (t1, . . . , tnw) ♥ ♥♥ t s ♥♦t U ∈ R
r×1 t tr s tt ♦sr t t♠ tu > tnw
♦r t r rs ♥ ts ♥ ♥ ❲ ss♠ tt
(W′U
′)′= Aθ + Zψ + ε
r Z = (Z′w Z
′u)
′ A = (A′w A
′u)
′ r ♥♦♥ ♠trs ♥ ε = (ε′w ε′u)
′ r♥♦♠ ♠tr①(W′
U′)′ s ss♠ t♦ ♥♣♥♥t ♦ t Yis ❲ r ♦♦♥ ♦r r♦♥ Rα
ξ (W) s♦tt P
(U ∈ Rα
ξ (W)∣∣W)= 1− α.
♦ s r♦♥ ♥ t♦ t♥s r♥♦♠ s♠♣ ♦ ♥s (Yi)i∈1,...,N
tt ♥s t ♣♦♣t♦♥ ♣r♠trs ξ t♦ st♠t ♥ s♦♠ ♦srt♦♥s ♣r♦r♠♥ t ♥ ♦ ♥trst W ❲ ♣r♦ ♥ tr st♣s rst r♦♥ Rα
ξ (W)
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② ss♠♥ tt ξ s ♥♦♥ s♦♥② ♣♥ t st♠t ξ ♦ ξ ♦t♥ s♥ ts♠♣ (Yi)i∈1,...,N ♥t♦ Rα
ξ (W) t♦ t Rαξ(W) ♦rs s t st♠t ξ s
r♥♦♠ r ts ♣♥ st♠t♦r ♦s ♥♦t r♥t ♦r ♦ 1 − α. s s trs♦♥ ② ♣r♦♣♦s ♥ ♦♠♣r tr r♥t ♦rrt♦♥s ♦r t st♠t ♣rt♦♥r♦♥ s♥ ts ♣♥ st♠t♦r ♥ t tr st♣
st♠t♦♥ ♦ ♣r♠trs
t s ♥♦t Λi = Λi(ρ,Σ)) = var (εi) ss♠ ♦r tt t ♣r♠tr ξ s ♥♦♥♥ q t♦ ξ0 = (θ0,Ω0,Σ0,ρ0) ♥
(Y i −Aiθ0
Ψi
)∼ N
(0,
(ZiΩ0Z
′i +Λi ZiΩ0
Ω0Z′i Ω0
))
s♦ ② r ♠♠ ❩♥ ♦t♥
mi,0= Eξ0
(Ψi|Y i −Aiθ0) = Eξ0(Ψi|Y i) = Ω0Z′i [ZiΩ0Z
′i +Λi]
−1[Y i −Aiθ0]
V i,0= Vξ0(Ψi|Y i) = Ω0 −Ω0Z
′i [ZiΩ0Z
′i +Λi]
−1ZiΩ0.
♦ st♠t t ♣r♠tr ξ ♣r♦♣♦s t♦ s t ♦rt♠ ♠♣str t t trt♦♥ k ξk−1 s ♦rt♠ tr♥ts t♥ t♦st♣s t st♣ ♦♠♣ts Q(ξ, ξk−1) = E
[logL (Y 1, . . . ,Y n; ξ) |Y 1, . . . ,Y n; ξk−1
]♥
t st♣ s♦s ξk = arg supξQ(ξ, ξk−1). s t Y i r ♥♣♥♥t Q(ξ, ξk−1) =∑i Eξk−1
[logL(Y i,Ψi)|Y i] .♠♥♥ tt
−2 logL(Y i,Ψi) = (Y i −Aiθ −ZiΨi)′Λ
−1i (Y i −Aiθ −ZiΨi)+log |Λi|+Ψ
′iΩ
−1Ψi+log |Ω|,
ts ♦t♥
−2Q(ξ, ξk−1) =N∑
i=1
tr(Λ−1i ZiV i,k−1Z
′i) + (Y i −Aiθ −Zimi,k−1)
′Λ
−1i (Y i −Aiθ −Zimi,k−1)
+ tr(Ω
−1V i,k1
)+m′
i,k−1Ω−1mi,k−1 + log |Λi|+ log |Ω|.
♠♥♠③t♦♥ ♦ −2Q(ξ, ξk−1) t rs♣t t♦ Ω ♥ θ s rs♣t② t♦
Ωk =1
N
N∑
i=1
[V i,k−1 +mi,k−1m
′i,k−1
],
θk =
(N∑
i=1
A′iΛ
−1i Ai
)−1 N∑
i=1
(A′
iΛ−1i (Y i −Zimi,k−1)
).
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t s ♥♦t U i = Y i −Aiθ −Zimi,0 ♥ P i = ZiV i,0Z′i +U iU
′i ❲ ♥t t♦ ♦♠♣t
argminΣ,ρ
−2Q(Λ,Λ0) = argminΣ,ρ
tr
(N∑
i=1
Λ−1i P i
)+
N∑
i=1
log |Λi|
tt sargmin
Σ,ρ−2Q(Λ,Λ0) = argmin
Σ,ρtr
(N∑
i=1
DiRiDiP i
)− 2
N∑
i=1
log |Di|.
t s ♥♦t J j,i =δD−1
i
δσ−1
j
❲
−2∂Q
∂σ−1j
= 2
[N∑
i=1
tr(DiFji )−
ni
σ−1j
]
r F ji = P iJ j,iRi s nir×nir ♦♣rtt♦♥ ♠tr① t ni×ni ♠trs
(f
ji
)k,l∈1,...,r
.
s
−2δQ
δσ−1j
= 2r∑
k=1
N∑
i=1
(σ−1k tr
[(f
ji
)kk
]− ni
σ−1j
)
♥ t r♠♥s t♦ s♦ t s②st♠ ♦ qt♦♥s δQ
δσ−1
j
= 0, j = 1, . . . , r t♦ t t ♠①♠♠ ♦
Q t rs♣t t♦ σ−11 , . . . , σ−1
r ♦s② ts s②st♠ s ♥♦t ♥r ♦r ♥ ♥♦ttt t rts s x′B = 1/x r
x′ =(σ−11 , σ−1
2 , . . . , σ−1r
), 1/x = (σ1, σ2, . . . , σr) ♥ B =
(∑Ni=1 tr
[(f
ji
)kk
]∑N
i=1 ni
)
j,k∈1,...,r
,
♥ s♦ trt② s♥ t rrs♦♥ ♦r♠ xmB = 1/xm+1s ①♣♥ ♥ t♦♥ αjk ♥ ρjk s ♥ [−1, 1] ∀j, k ∈ 1, . . . , r s ♥ s②♦♣t♠③ ♥♠r② Q ♦♥ ts ♥tr t♦ ♦t♥ t st♠ts ♦ αjk ♥ ρjk ♦♦ ♦ ♦ strt♥ s s♣s ♣ t ♦♥r♥ ♦ ts ♦rt♠ s strt♥s ♥ s② r r♦♠ ♥rt ♥②ss ♥②ss ♦ t jth r s♥♠♦ s βj ♥ Φij ζij ♦r i ∈ 1, . . . , N ♠♣r r♥ ♦ Φij ♥
s s strt♥ ♦ Ω βj ♥ s ♦r βj trt♥ s ♦r ♥tr♥r♥ ♦♠♣♦♥♥ts ♥ ♦t♥ s ♦♦s
Σjj′ =N∑
i=1
ni∑
k=1
ζijkζij′k/(niN), σj =√
Σjj, αjj′ = Σjj′/(σjσj′).
strt♥ s ♦r ρjj′ r ♦♠♣t ② ♠①♠③♥ t ♦♦ ♦t♥ ② ss♠♥tt ζi r strt ♦r♥ t♦ N (0,Λi(ρ,Σ)) r♥ ts ♠①♠③t♦♥ Σ sst t♦ ts ♥t ♦♠♣tr t♠ ♥ ♦r ♣r♠tr st♠t♦♥ s ss t♥ ♦♥s♦♥ s♥ ♥ ♦r♥r② ♣t♦♣
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♥ ♣rt♦♥ r♦♥s
♠♥ tt ss♠ tt ♦srt♦♥s W ♦r t r rs r ♥ ♥♥ ❲ r ♦♥ t♦ ♣rt♦♥ r♦♥ ♦r t ♥①t ♦srt♦♥ U ♦r ts ♥♥ r♦♠ t ♠♦ ♥ ♥
U = Auθ +Zuψu + εu.
♦r♥ t♦ t♦♥ ss♠ ♥ ts st♦♥ tt t ♠♦ ♣r♠trs r ♥♦♥❲ ♥♦t
E = vec(εw, εu) ∼ N
(0;
(Λw(ρ,Σ) Mwu(ρ,Σ)′
Mwu(ρ,Σ) Λu(ρ,Σ)
))
r Λw(ρ,Σ) ♥ Λu(ρ,Σ) r ♥ ♥ t rst st♦♥ ♥ Mwu(ρ,Σ) s r × (rnw)♠tr① t
Mwu(ρ,Σ) = ♦ (εw; εu) =
♦(ε1u; ε
1k=1,...,nw
). . . ♦
(ε1u; ε
rk=1,...,nw
) . . .
♦(εru; ε
1k=1,...,nw
). . . ♦
(εru; ε
rk=1,...,nw
)
r εiu s t it tr♠ ♦ εu ♥ εjk=1,...,nws nw ♠♥s♦♥ t♦r ♦r r j ♥
♥ W ♥
♦(εiu; ε
jk=1,...,nw
)=(Σijρ
|tu−t1|ij , . . . ,Σijρ
|tu−tnw |ij
).
❯s♥ ts ♥♦tt♦♥s ♥ r ♠♠ ♦t♥ t ♦♦♥ ♣r♦♣♦st♦♥
Pr♦♣♦st♦♥ t α ♥② r ♥♠r ♥ [0; 1] ♥ χ2r,1−α t 1 − α q♥t ♦
sqr strt♦♥ t r rs ♦ r♦♠ t s ♦♥sr t t♦r m(ξ,W ) ♥
t ♠tr① V (ξ) ♥ ②
m(ξ,W ) = Auθ + (ZuΩZ′w +Mwu(ρ,Σ)) (ZwΩZ
′w +Λw(ρ,Σ))
−1(W −Awθ) ,
V (ξ) = (ZuΩZ′u +Λu(ρ,Σ))
− (ZuΩZ′w +Mwu(ρ,Σ)) (ZwΩZ
′w +Λw(ρ,Σ))
−1(ZuΩZ
′w +Mwu(ρ,Σ))
′.
(1− α) ♣rt♦♥ r♦♥ ♦ U ♦♥t♦♥② t♦ W s t st
S =u ∈ R
r; ‖V (ξ)−1/2 (u−m(ξ,W )) ‖2 ≤ χ2r,1−α
r V (ξ)−1/2 s t ♥rs ♦ t ♦s② tr♥s♦r♠t♦♥ ♦ V (ξ).
❲♥ r > 1 t ♣rt♦♥ r♦♥ ♦r U s ts ♥ ♣s♦ ♥tr ♦♥ m(ξ,W ) s
♣s♦ ♥rts t♦ t ♥tr[m(ξ,W )− τ(1−α/2)
√V (ξ);m(ξ,W ) + τ(1−α/2)
√V (ξ)
]
r τ(1−α/2) s t (1−α/2) q♥t ♦ t st♥r ss♥ strt♦♥ ♥ ♦♥ ♥ts
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t♦ ♣rt t ♥①t U ♦ s♥ r r = 1♥ ts s ρ = 0 ♥ ss♠♥ tt tr s ♥♦ ♦r t jt ♦srt♦♥ ♥ t it
♥ rtsXij = Yij = θ + ψi + εij
t ψi ∼ N (0, ω2) ♥ εij ∼ N (0, σ2) . ❯s♥ r ♦♠♣♠♥t t 100(1−α) ♣rt♦♥♥tr ♦r t tr ♥ k − 1 ♦srt♦♥s r r② ♥ ♥ ♥s t ♦♦♥ ①♣rss♦♥
[θ
1 + γ2(k − 1)+
γ2(k − 1)
1 + γ2(k − 1)W k−1 − τ(1−α/2)
√1 + γ2k
1 + γ2(k − 1)σ2,
θ
1 + γ2(k − 1)+
γ2(k − 1)
1 + γ2(k − 1)W k−1 + τ(1−α/2)
√1 + γ2k
1 + γ2(k − 1)σ2
],
r γ = ω/σ ♥ W k−1 s t r ♦ t k − 1 ♦srt♦♥s ♦t tt γ♠srs t ♥t ♦ t ♥③t♦♥ ♦♠♣r t♦ t s rr♥ ♥tr tt s♥ ♣r ♥ ❲♥ γ s t ♣rt♦♥ ♥trs ♦s t♦
[W ± τ(1−α/2)σ
]♥ t ♥③t♦♥ s ♥ ❲♥ k = 1 ♥
♥♦ ♦srt♦♥ s ♦r t ♥ ♥ t ♥tr ♥rts t♦ t s[θ ± τ(1−α/2)
√σ2 + ω2
] s ts ♠♦ ♦s ♥♦t ♥ ♥② ♦rrt♦♥ t♥ ♦srt♦♥s
t♥ ♥ t t♠ ♥tr t♥ ♥ ♦srt♦♥ ♥ tr ♦s ♥♦t♠♦② t t ♦ t ♣rt♦♥ ♥tr ♣♥ st♠t♦r ♦ S s S ♦t♥ ② r♣♥ ♥ qt♦♥ t ♣r♠tr ξ ② tsst♠t ♦t♥ ♣rt♦♥ r♦♥ s t♦ r♥t ♥ ①t ♦r ♦ (1−α) s♦rs ♥ t s♠♣ s③ n s ♦ ♥ t♦ s♦♠ ♠♣rs st♠t ♦r ξ ♦ ♣r♥tts ♣r♦♠ ♣r♦♣♦s r♥t strts t♦ ♦rrt t ♦r ♦ ♦r ♣rt♦♥ r♦♥
P♥ ♦rrt♦♥s
t s ♥ KW (ξ0, ξ) = ||V −1/2(ξ) (U −m(ξ,W )) ||2 r (U |W ) ∼N (m(ξ0,W ),V (ξ0)) t s ♦♦s tt ♦r ξ KW (ξ, ξ) s r♥♦♠ rstrt ♦♥t♦♥② t♦W ♦r♥ t♦ χ2 strt♦♥ s s ♥♦ ♦♥r t s ♦rKW (ξ0, ξ) t ξ n ♦♥sst♥t st♠t ♦ ξ t ♥♦♥ strt♦♥ L s (W ′U ′)
′
s ss♠ t♦ ♥♣♥♥t ♦ t ♦srt♦♥s Y i (W ,U ) ♥ ξ r ♥♣♥♥t ❲
♥t t♦ st♠t xα,ξ0,ξ,Ws tt P
(KW
(ξ0, ξ
)≤ xα,ξ0,ξ,W
∣∣∣W)
= 1 − α ❲ ♥
♥ t ♦♦♥ sst♦♥s tr r♥t ♦rrt♦♥s ♥♦t ② x1α,ξ0,ξ,W
x2α,ξ0,ξ,W
♥ x3α,ξ0,ξ,W
♦rt ♣r♦♣rts ♦ ts ♦rrt♦♥s r ♥♦t sss r
♥ rr t ♥trst rr t♦ t rr♥s r♥ t ❯ ♥ ❱♦♥ ♦♥s t
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rst ♠t♦
r♦ st♠t♦♥ x4α,ξ,ξ
♦ xα,ξ0,ξ,W♥ ♦t♥ ② ss♠♥ tt t t r r♥
r♦♠ strt♦♥ t ♣r♠trs ξ ♥st ♦ ξ0 s KW
(ξ, ξ)
s strt ♦♥
t♦♥② t♦ W ♦r♥ t♦ χ2r strt♦♥ x4
α,ξ,ξ= χ2
r,1−α t (1 − α)q♥t ♦ ts
strt♦♥ s ξ s t ♠①♠♠♦♦ st♠t ♦ ξ0 t s rst ♦rrr② ❯ ♥ ❱♦♥ ♦♥s t ♥
1− α+ (ξ0,W ) = Pξ0
(KW
(ξ0, ξ
)≤ x4
α,ξ,ξ|W)= 1− α+ δ (ξ0,W ) /N +O
(N−3/2
).
t ♦♦s tt
Pξ0
(KW
(ξ0, ξ
)≤ x4
α−δ(ξ0,W )/N,ξ,ξ|W)= 1− α +O
(N−3/2
).
❲ ts ♦t♥ tr ♦rr r② ② ♦rrt♥ α ② δ(ξ0,W )/N t
δ(ξ0,W )/N =(1− α+(ξ0,W )
)− (1− α) +O
(N−3/2
).
s ξ0 s ♥♥♦♥ ts ♦rrt♥ tr♠ s s♦ ♥♥♦♥ ♦r ♥ st♠t t ②
s♥ ♣r♠tr ♦♦tstr♣ ♠t♦ ♥ t♦(1− α+(ξ,W )
) ♦
δ(ξ,W )/N =(1− α+(ξ,W )
)− (1− α) +O
(N−3/2
)
♥ s δ(ξ,W )− δ(ξ,W ) = O(1/√N) ♦t♥ δ(ξ,W )/N = δ(ξ,W )/N +O
(N−3/2
).
♦ t r♠♥s t♦ t 1 − α+(ξ,W ) ♠♥ tt ξ∗ s ♦♦tstr♣ s♠♣ ♦ ξ
s②♠♣t♦t② L
(ξ|ξ0
)≈ L
(ξ∗|ξ
) r ♦♣t♦♥s rst ♥♦
tt ξ − ξ0 ∼ N(0, I−1/2(ξ0)/N
)s ♥tr ♠t t♦r♠ ♥ s (ξ∗ − ξ)|ξ ∼
N(0, I−1/2(ξ)/N) r ξ∗ ♥ N(ξ, I−1/2(ξ)/N) strt♦♥ ♥ t s♦♥ ♦♣t♦♥ s♠t (Y ∗
i )1≤i≤N s♥ t strt♦♥ ♦ (Y i)1≤i≤N t ♣r♠tr ξ ♥ t ξ∗ ②st♠t♥ t ♣r♠tr ♦ t ♠♦ s♥ (Y ∗
i )1≤i≤N ♥st ♦ (Y i)1≤i≤N
❯s♥ qt♦♥s ♥ ♥ s KW
(ξ, ξ∗
)= || (V (ξ∗))−1/2 (U −m(ξ∗,W )) ||2 r
U ∼ N(m(lξ,W );V (ξ)
) st ♦ (ξ∗h)1≤h≤H ♥ tt
1− α+(ξ,W ) =1
H
H∑
h=1
1
L
L∑
l=1
1[||(V (ξ∗h))
−1/2(U l−m(ξ∗h,W ))||2≤x4
α,ξ,ξ
]
r H ♥ L r rs♣t② t ♦♦tstr♣ s♠♣ s③s ♦ (ξ∗) ♥ U ❲ ♦♥ tt
x1α,ξ0,ξ,W
= x4α−δ(ξ,W )/N,ξ,ξ
+O(N−3/2
).
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♦♥ ♠t♦
t Fξ0,W (x) = P(KW (ξ0, ξ) ≤ x|W
) ❲ ♥t x2
α,ξ0,ξ,Ws tt Fξ0,W
(x2α,ξ0,ξ,W
)=
1− α t Fξ0,W s ♥♥♦♥ s s♦♥ ♥
1− α+(ξ0,W ) = Fξ0,W
(x4α,ξ,ξ
)= 1− α +
δ(ξ0,W )
N+O
(N−3/2
).
♦♥sq♥t② ♦t♥
x2α,ξ0,ξ,W
= F−1ξ0,W
(1− α) = F−1ξ0,W
1− α+(ξ0,W )− δ(ξ0,W )/N +O
(N−3/2
)
♦s s②♠♣t♦t ①♣♥s♦♥ s
x2α,ξ0,ξ,W
= F−1ξ0,W
1− α+(ξ0,W )
− δ(ξ0,W )
N[F−1
ξ0,W]′1− α+(ξ0,W )
+O
(N−3/2
).
t s s t♦
x2α,ξ0,ξ,W
= x4α,ξ,ξ
− δ(ξ0,W )
Nfξ0,W (x4α,ξ,ξ
)+O
(N−3/2
)
r fξ0,W s t ♣r♦t② ♥st② ♥t♦♥ ♦ KW
(ξ0, ξ
) ♦rs fξ0,W s ♥♥♦♥
t s t ♠♦ s rr ♦r x(fξ0,W (x)− f
ξ,W (x))= O (1/
√n) . ❲
s♥ ♥ t ♣r♦s st♦♥ tt KW
(ξ, ξ)s r♥♦♠ r strt ♦r♥
t♦ χ2 strt♦♥ ♦♥sq♥t② t ♣r♦t② ♥st② ♥t♦♥ ♦ t χ2 strt♦♥♥ ♣♣r♦①♠t fξ0,W ♥ ♣ ♥t♦ t♦
x2α,ξ0,ξ,W
= x4α,ξ,ξ
− δ(ξ0,W )
Nfξ,W (x4
α,ξ,ξ)+O
(N−3/2
).
t r♠♥s t♦ st♠t δ(ξ0,W ) tt ♥ ♦t♥ s t t ♣r♦s ♠t♦
r ♠t♦
rst t♦ ♠t♦s ♥ r s t♠t♦s tr ♠t♦ s ♥ ♣♣t♦♥ ♦ s♠♣ ♣r♠tr ♦♦tstr♣ ♠t♦ s ①♣♥ ♥ t rst ♠t♦ ♦r x
Fξ0,W (x) = P(KW
(ξ0, ξ
)≤ x|W
)≈ P
(KW
(ξ, ξ∗
)≤ x|W
).
r♦r s♥ ♥♦tt♦♥s ♦ ♣r♦s sst♦♥s Fξ0,W (x) ♥ st♠t ②
Fξ0,W (x) =1
H
H∑
h=1
1
L
L∑
l=1
1[||(V (ξ∗h))
−1/2(U l−m(ξ∗h,W ))||2≤x
].
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♥♦t♥ F−1(y) = infx : F (x) ≥ y
x3α,ξ0,ξ,W
≈ F−1ξ0,W
(1− α).
s sss ♥ ♦♥s t ts ♥ s ♥ ♥ t Pr♦♣♦st♦♥ ♦ r♥ tt s♦s tt
P(KW (ξ0, ξ) ≤ x3
α,ξ0,ξ,W|W)= 1− α +O(N−2).
strt♦♥s
tst
t ♦♠ r♦♠ ♣r♦s♣t st② ♠ t t♥ rt♦♥s ♦r t♠ ♦ sr♦♠ rs ♥ t② ts s st② s rr ♥ t ♥s ♦ t ❱tr♥r②♦ s② r s ♥♠s ♦r t② ♥♠s ♦r str③t♦♥ ♦♦s②♦♥② ♦♥ s s t rs♦♥ ② ♦♥② N = 20 t② ts ♦ ♥ ♥ ♥ts st② ♠♥ rs ♦r r♥ ♦♦♣ r t r X1 t rt♥♥ X2 ♥ t♣r♦t♥ X3 r ♣♦tt ♥ r ♦r t 20 t② ts r s ♥♦ rs♦♥ t♦ t♥tt ts rs r ♥♦t st ♦r t♠ ♥ t② ts ②♥♦s t r ❯♥rt ♥②ss r ♣r♦r♠ ♥ t t ♦ t♠ s ♦♥ ♥♦t s♥♥tr② t t tr r ♠sr t♠s 0 3 6 12 ♥ 24 ♠♦♥ts tr ♥s♦♥ r♠♥♥ tr r s♠♣ ♦♥② ♦r t rst ♦r t♠s ♦t tt t ♥tr st②s ♣r♦r♠ ♦♥ t ♦ tr♥s♦r♠t♦♥ ♦ t rs s s♦ ♦r♥ t♦ t♦♥ ♣r♦♣♦s t ♦♦♥ ♠♦
X i = Biβ + T iΦi + ζi
r X i s ni × 3 ♠tr① t ni t ♥♠r ♦ ♦srt♦♥ ♦r t it t ♦r Bi ♥ T i r t♦rs ♦ ♥t ni s tt Bi = T i = (1, . . . , 1) β = (β1, β2, β3) ♥φi = (φi1, φi2, φi3) ♥ ζi s ni × 3 ♠tr① ♦r♥ t♦ t♦♥ ♥ ts ♣♣t♦♥ ni = 4 ♦r 5 r = 3 p = 1 q = 1 ♥ N = 20 s ♥♦ ♦r s① t ♠tr① Bi ♦s ♥♦t ♥♦r♣♦rt ♥② ♥♦r♠t♦♥ t ts ♥ ♦ ♥♦r♠t♦♥ ♥s② ♥srt ♥ ♦r ♠♦ s ♥ ♦tts t
st♠t♦♥ ♦ t ♣r♠trs
❯s♥ t ♠t♦ ♣r♦♣♦s ♥ t♦♥ st♠t t ♣r♠trs ♥ ♦♥ t ♦♦♥s σ1 = 0.083 σ2 = 0.062 σ3 = 0.032 θ1 = 2.054 θ2 = 4.834 θ3 = 4.368
α =
10.306 10.074 0.211 1
ρ =
0.411 0.001 0.0100.013 0.005 0.0100.009 0.896 0.005
♥ Ω =
0.0220.011 0.015−0.001 −0.001 0.003
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♦ strt t s ♦ ts st♠ts r r st♠ts ♦ ♦rrt♦♥s t♥ r 2♥ 3 t t♠s t ♥ ♠♦♥ts ♥ t′ > t rr ♦t ♥ t s♠ ♥
ω23 =
1
ρ t′−t22 1
α23 α23ρt′−t32 1
α23ρt′−t23 α23 ρ t′−t
33 1
=
10.005t
′−t 10.211 0.211 ∗ 0.896t′−t 1
0.211 ∗ 0.010t′−t 0.211 0.005t′−t 1
.
♥ ts ①♠♣ t ♦rrt♦♥ t♥ t♦ sss ♠sr♠♥ts rr ♦t ♥ t s♠♥ s rtr ♦ ♦r ♣rt s t t′− t > 1 ♠♦♥t ♦r sr♣rs♥② t ♣♣rstt ♥♦ r s ♥ rr ♠rr t♥ t ♦trs t♦ tt ♥② ♥s♥② ♥ ♦tr♦rs tr s ♥♦ ♠♦r ♦rrt♦♥ t♥ t♦ r♥t rs t t♦ r♥t t♠ss rst ♦ ♥♦t ♥t♣t ❲t ts rst t ♥t ♦ t ♥③t♦♥♥ r♦② ♠sr ② t rt♦ γ = ω/σ s s q t♦ 1.8 2.0 ♥ 1.7♦r r rt♥♥ ♥ ♣r♦t♥ rs♣t② s ts rt♦s r rtr t♥ ♦♥ ♦♥ ♥①♣t t ♥③ r♦♥ t♦ ♥rr♦r t♥ t ♣♦♣t♦♥ ♦♥tr♣rt
♦♠♣rs♦♥ ♦ t tr ♦rrt♦♥s
s ♦r rst ♠♦tt♦♥ s t♦ ♣r♦♣♦s rr♥ r♦♥ ♦r rs ♠sr♥ ♥② ♥s♥② ♥ ts ♦♠♣r t tr ♣r♦♣♦s ♦rrt♦♥s ♥ ts ♦♥t①t ♦♦♠♣r t tr r♥t ♦rrt♦♥s ♦t♥ t t tr ♣r♦♣♦s ♠t♦s ♥t st♥r χ2 trs♦ x4
α,ξ,ξt♦t ♦rrt♦♥ rr ♦t s♠t♦♥ st②
♦ ♦ t st② s t♦ ♦♠♣r P(KW
(ξ0, ξ
)≤ x
∣∣∣W)
♦r x ♥ t stx1α,ξ0,ξ,W
,x2α,ξ0,ξ,W
,x3α,ξ0,ξ,W
,x4α,ξ,ξ
♦ rst ♥ t♦ ♥♦ ξ0 = (θ0,Ω0,Σ0,ρ0) ♥
t ξ0 s t ♠①♠♠ ♦♦ st♠t ♦r ξ ♥ t ts tst ❯s♥ ξ0
s♠t 500 ♥ tsts((Y k
i
)i=1,...,20
)k=1,...,500
, r(Y k
i
)s t t♦r ♦ s③ rni = 15
♦♥t♥♥ t s ♦ t tr rs t t s♠♣♥ t♠s ♦r t it t ♦ t kt
tst tr ♦rrt♦♥s ♥t t♦ ♦♠♣r ♣♥s ♦♥ t ♣st s ♦sr ♥t ♥ ♦ ♥trstW s ♥t t♦ ♦♠♣r t r ♣r♦r♠♥s ♦ ts♦rrt♦♥s ♦s t♦ ①♣♦r t ♣♦ssW s tt ♦ ♦sr ♥ ♥ ♥ s s t rs♦♥ ② ♦r tst ♦s t♦ ♣rt ♦r s♥ t t sU k r♦♠W k ♦♥t♥s t nw = 4 ♠sr♠♥ts t 0 3 6 ♥ 12 ♠♦♥ts ♦r t trrs ❲ s♠t 5000 ♣rs (W k,U k) r♥ r♦♠ N (Awθ0,ZwΩ0Z
′w +Λ(ρ0,Σ0))
rU k ♦♥t♥s t ♦rrs♣♦♥♥ ♠sr♠♥ts t t♠ tu = 24♠♦♥ts ♦r tst((Y k
i
)i=1,...,20
)k rst ♦♠♣t t ♠①♠♠ ♦♦ st♠t ξk ❲ t♦♦ H = 200
♥ L = 1 t♦ ♦♠♣t t tr ♦rrt♦♥s ♥ ♦r tst k ♦♠♣t ♦rr
t♦♥(xlα,ξ0,ξk,W k
)l=1,2,3
♥ t ss x4α,ξk,ξk
tt ♦s ♥♦t ♣♥ ♦♥ W k ♦t
tt ♦♥② ♣r♦r♠ ♦♥ st♠t ♦ t ♦rrt♦♥s ② ♦♦tstr♣ s♠♣ ♦♥t♦♥② t♦W k t ♣rt♦♥ r♦♥s r t♥ t ♥ tr ♦r ♥♦t U k ♦♥t♦ ts r♦♥s
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♥② st♠t P(KW (ξ0, ξk) ≤ x
)② ts ♠♣r r rs♦♥
1
5000
5000∑
k=1
1[KW (ξ0,ξk)≤x]
♦r x ♥ t stx1α,ξ0,ξk,W k
,x2α,ξ0,ξk,W k
,x3α,ξ0,ξk,W k
,x4α,ξk,ξk
rsts ♦ ts
♦rrt♦♥s r s♦♥ ♥
♦♠♣rs♦♥ ♦ r ♦r ♣r♦ts st♥r t♦♥s ♦r t tr♦rrt♦♥s ♥ t st♥r χ2 trs♦ ♦r α = 0.95
t♦ 1st ♦rrt♦♥ 2♥ ♦rrt♦♥ 3r ♦rrt♦♥ t♥r χ2
♦r ♣r♦t②
❲ ♥ ♥♦t tt t tr ♦rrt♦♥ s t ♥rr♦r ♣rt♦♥ r♦♥ ♥ t s ♦x4α,ξ,ξ
t ♠♣rs♦♥ ♦ t st♠t♦♥ s ♥♦t t♥ ♥t♦ ♦♥t ♥ t ♦♠♣tt♦♥ ♦ t♣rt♦♥ r♦♥ ♥ t♦ s♠ ♣rt♦♥ r♦♥ s s ♥♦t t s ♦r t rst ♥t s♦♥ ♦rrt♦♥ tt ♦s rsts ♦♥trr② t♦ t rsts ♦t♥ ② ❱♦♥ t② ♦t ♦rst♠t t ♦r ♥ t♦ ♣rt♦♥ r♦♥s ♦t tts♠r rsts r ♦t♥ ♦r ♦tr ♦♥♥ s ♦♠♣r♥ t r ♦r♣r♦ts s rt♥② sr t t ♦s ♥♦t ♦ t s③ ♦ t ♣rt♦♥ r♦♥st♦ ♦♠♣r s ② r♣rs♥t t strt♦♥s ♦ t ♦rrt♦♥s ♥ r ♦r ♥ ♦ ξk t s③ ♦ t ♣rt♦♥ r♦♥ s ♦r♥ ② t r♥t xl♥ ♦rrt♦♥ ♦ ♥♦t ♥ssr② ξ0 r ♥♦♥ ♥ ♥♦t st♠t r t
♥♦ ♦ ξ0 ♥s t trt q♥t t♦ t ♦r (W k, ξk
) ♥
♦♥sq♥t② t ♦♣t♠ s③ ♦r t ♣rt♦♥ r♦♥ ♦♥t♦♥♥ ♦♥(W , ξ
)s
t strt♦♥ ♦ t t q♥t ♥ r ♥ r s strt♦♥ s st♠t
♠♣r② t 5000 s ♦(W k, ξk
) s ♥ s t strt♦♥ ♦ x3 s ♦r
r♥ t♥ t ♦trs tt ♥srs s♠ rt♦♥ ♦ t ♣rt♦♥ r♦♥ s③ r♦♠ ♦♥s♠♣ t♦ ♥♦tr tr♠♦r ts strt♦♥ s t ♦sst t♦ tt ♦ t t q♥t♦r♥ t♦ ts s♠t♦♥ st② ♣r♦ rsts ♥ t ♥①t st♦♥ s♥ t tr♦rrt♦♥ x3
α,ξ0,ξ,W♥ t t s t r ♦ 5000 ♦♦tstr♣ s♠♣s ♦t
tt t st ♣r♦r♠♥s ♦ t tr ♠t♦ r ♦♥② sts r ♦r t s tst♥ ♦ ♥♦t tr ♥ ♥r ♣♦ss ①♣♥t♦♥ ♦ tt t rst ♦rrt♦♥ s
s ♦♥ χ2 ♣♣r♦①♠t♦♥ ♦r t strt♦♥ ♦ KW
(ξ0, ξ
)♥ ♦♦tstr♣ st♠♥t
♦r t trt ♦r rtr♠♦r t s♦♥ ♦♥ s tr♥t s②♠♣t♦t ①♣♥s♦♥ ♦t rst ♦♥ ♥ ♦♥sq♥t② s ss rt ② ts r② ♦♥strt♦♥ t tr ♦rrt♦♥s ①♣t t♦ t st ♦♥ s t ♦s ♥♦t ♣r♦r ss♠ χ2 strt♦♥ ♦r
KW
(ξ0, ξ
) ts ♦♥② ♣♣r♦①♠t♦♥ s t♦ ssttt t r strt♦♥ ♦ ξ ② ts ♦♦tstr♣
♦♥tr♣rt s ①♣t t s ♦r ♣r♦t② r② ♦s t♦ t trt ♦♥
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Prt♦♥ r♦♥
❲ ♥ t ♦r ♣♦ssss ♦r ♠sr♠♥ts t 0 3 6 ♥ 12 ♠♦♥ts ♦r r ❯s♥ t ♣r♦♣♦s ♠t♦ ♥ ♥ ♥ rr♥ r♦♥ ♥♣s♦ ♦r tr s ♦r ts rs ts tr ♠srs ♦ts ts r♦♥ts t s ♦ ♣r♦t② ♦ ♥ t② rsts ♦♥ ts ♥ t r ♣♦tt ♥r s ♥♥s r ♥♦t st♦♠ t♦ ♠tr① s t s ♥♦t s② t♦ tr ♦r ♥♦t ♥ ♣♦♥t ♦♥ t ♥ t ♦♥s t♦ ts ♣rt♦♥ r♦♥ s s t
rs♦♥ ② ♣r♦♣♦s t♦ r♣rs♥t t ♣r♦t♦♥ ♦ t ♣s♦ KW
(ξ0, ξ
)≤ x3
α,ξ0,ξ,W
♦r r s s ♥ ♥tr ♦ ♣rt♦♥ ♦r r ♥ tr t♠♦ ♠sr♠♥t ♦t tt ts ♥trs r ♣rs♥t t♦ r♣ r♣rs♥tt♦♥s t② r ♦t♥ ② ♣r♦t♦♥ t② ♦ ♥♦t r♥t t rt ♦r ♦♥trr② t♦t ♣s♦s ♥ ② Pr♦♣♦st♦♥ ♦ t② ♥ ♥♦t s s♣rt② t♦ ♥♦s t s t tr rs r str♦♥② rt s s♦♦♥ s ♦ r s ♦ts t♣rt♦♥ r♦♥ t t ♥ ♦♥sr s ♣r♦② ♥♦t t②❲ ♥ r♠r tt ♦r ♣rt♦♥ ♥trs r r② r♥t ♥ ♥rr♦r t♥ t s♦ rr♥ ♥trs ♥ tr♦r t♦ r♥t ♥ s♦♥s s ♥ ①♠♣ ♦rt♥♥ ♦ t t♥ ♠♦♥ts ♦ tt s ss♣♦s ♦r t ♥ ts♥ t st♥r rr♥ ♥trs t ♥③t♦♥ ♦s ♥♦t trr s s r♠ ♥ t ♦tr ♥ ♦❯r ♦ ♦ tt s ♥♦r♠② ♦r ♠t♦ t ♥♦t ② t s rr♥ ♥trs rt♦♥ ♦ t ♦r t♣rt♦♥ r♦♥ rss t ♣r♦t② ♦r ♥ ♦ ♥ tt s s♥t s♣t t ♦♥sr r♥ t♥ t χ2 trs♦ x4
α,ξ,ξ♥ x3
α,ξ0,ξ,W
t ♦rrs♣♦♥♥ ♣rt♦♥ r♦♥s r r② ♦s ♥ ts s ts ♥ ①♣♥② s♠ r♥ ♥ tr ♦♥t♦♥ ♦♥ t ♦srt♦♥s s ♥♥♦t s② ♥t♣t ② s♠♣ ♥ ♦♥ t ♣r♠tr st♠t♦♥s s ts ♦♥t♦♥ r♥♣♥s ♦♥ ♦♠♣t ♥t♦♥ ♦ t r♥ ♣r♠trs s Pr♦♣♦st♦♥
sss♦♥
♥ ts ♣♣r ♥tr♦ ♥ ♠♦ t♦ ♣rt♦♥ r♦♥s s ♣♣r♦ s ♥s t s ♥③ ♥ ♠t♠♥s♦♥ ♥ r② ♥ ts ts ♦♥♣rt♦♥ r♦♥ ts ♥t♦ ♦♥t t ♣♦ss ♦rrt♦♥s t♥ t rst t r♥t t♠s s ♥ts ♥ s t♦ ♥rr♦r ♣rt♦♥ r♦♥st♥ t s rr♥ ♥trs ♠t♦ ❯s♥ ♦r ♠t♦♦♦② ♥♥s rtt ♠♦r ♣rs♦♥ t♦ ♣♦t♥t ♥t② ♥♠ ♦r ♣rs♦♥rtss ♦r ♠♦ s s ♦♥ str♦♥ ss♥ ss♠♣t♦♥ ♥ s ♥tr♥t ♦ t s ♦ ♥♦♥♣r♠tr r♠♦r t t ♦ ♥ ♠♦r ♥s♥ ② ♦♥sq♥ t ♥ ♥♦t ♣♣ t♦ ♦r ♣rt ♣r♦♠ s ss♠♣t♦♥ s s♦ ss ♦♥ t st ♣ t♦ ♦①♦① tr♥s♦r♠t♦♥ ♥ t ♦tr ♥ ♥ ss♠♣t♦♥ s s♦ ♠ ♦♥ t ①♣♦♥♥t rs ♦ t ♦rrt♦♥ ♦r t♠ tt ♥ ♣♣r rstrt ♦ t st ♦ ♦r ♥♦ ts ♥ ♦
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♣r♦♠ s r② ♥ ♠♦ ② ♥ AR(p)♣r♦ss ❲♥ ♥ ♥ ♥ ss♠♣t♦♥ t t♦ ♥ ts rs♣t t ♠♦ ♣r♦♣♦s ♥ s♥ ♥ ♦♥t♥♦s t♠s rst ♦rr ♣♣r♦①♠t♦♥ ♦ s ♥sr ♣r♠tr r♠♦r ♦s s t♦ s ♣♥ ♣♣r♦ ♦r t ♠♦ st♠t♦♥t t ♣♥ ♣♣r♦ s rr♦rs ♥ t st♠t♦♥ ♦ t ♣rt♦♥ r♦♥ ♥ st♦ r♥t ♥ ①t ♦r rt ♦ r♠♥t ts ♣r♦♠ s tr r♥t♦rrt♦♥s ♥ t ♠t♦ s♠s t♦ ttr rsts ♦♥ ♦r tst♥t② s♦♠ r♦st ①t♥s♦♥s ♦♥r♥♥ t ♠trt ♥r ♠① ♠♦ ♥♣r♦♣♦s s ①t♥s♦♥s r s ♦♥ t ♠trt t ♥ s ♥♦r♠ strt♦♥s♥ ♣r♦ ♣♣r♦s t ♠♦r ♥r ♠② ♦ strt♦♥s ❲♥ ♥ ♥ ❲♥ ♥ ♥ ❲♥ ♥ ♥trst♥ tr ♦r ♦ ♥ ①t♥s♦♥♦ ♦r rsts ♦r ts ♠♦s
r♥s
r♥♦rs♥ ♥ ♦① Prt♦♥ ♥ s②♠♣t♦ts r♥♦
r♥ rt♥ ♣rt♦♥ r♦♥s ♦r♥ ♦ t ♠r♥ ttst ss♦
t♦♥
t P♦st ♥t trs Pr♥t♦♥ rs ♥ ♣♣ t♠tsPr♥t♦♥ ❯♥rst② Prss
♥ ♥s ♦s ♦r ♦♥t♥ t t r♥♦♠ ts ♥ rr♦rs ♦r♥ ♦ t ♠r♥ ttst ss♦t♦♥
♥♥ sts♥ ♥ ❱r②♥ r♥ ♥trs ♥ t ♥ ♦
rt♦r② ♣♣r♦ ♥ ♦♠♥t ❲②♥ P
♥ ♥ t♥♥ ♦♥♥r ♠♦s ♦r r♣t ♠sr♠♥t t♦♥♦r♣s ♦♥ sttsts ♥ ♣♣ ♣r♦t② ♣♠♥ ♦♥♦♥ ❨♦r
♠♣str P r ♥ ♥ ①♠♠ ♦♦ r♦♠ ♥♦♠♣tt t ♦rt♠ ♦r♥ ♦ t ♦② ttst ♦t② rs
♦♥s ♠♠♦è ♥ ❱♦♥ P ♥♦t ♦t rt ♣rt♦♥ r♦♥s♥ strt♦♥s ♦r♥ ♦ ttst P♥♥♥ ♥ ♥r♥
♦♥s ♠♠♦è ♥ ❱♦♥ P rt♥ ♣rt strt♦♥s♦r♥ ♦ ttst ♦♠♣tt♦♥ ♥ ♠t♦♥
P P♥ ♥ ♥ ♣rt♦♥ ♥trs s ♦♥ ♣rt♦♦ ♦r ♦♦tstr♣ ♠t♦s ♦♠tr
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r P ♥ ♥t♦♥ tst♥ ♥ ♥ P t♦rs ♣r♦♦②♥ r♦♦② ♦ s♠ ♥♠s ♣s Ps♥ ♠s ❯
♥ ♥ ❲♥ ❲ trt s♥♦r♠ t ♥r ♠① ♠♦s ♦r♠t♦t♦♠ ♦♥t♥ t ttst ♦♥
②♥♦s ♦♥♦rt r♠♥ st ♦t ♥ r r ♣♥♥② ♦ rr♥ ♥trs ♦r ♣s♠ ♦♠ s ♥ ts ♦r♥ ♦❱tr♥r② ♥tr♥ ♥
♦tts P ♠ ♥ ③r ♠r ♥ ② ②s♥ tt♦♥ ♦ ♥♦r♠ s ♥ ♦♥t♥ ♦♠rrs t ♥ ♣♣t♦♥ t♦t rt♦ ♦sttsts
❯ ♥ st♥ st♠t ♣rt♦♥ ♠ts ♦♠tr
❱r ♥ ♦♥rs ♥r ♠① ♠♦s ♦r ♦♥t♥ t ♣r♥rrs ♥ ttsts ♣r♥r❱r ❨♦r
❱♦♥ P ♠♣r♦ ♣rt♦♥ ♥trs ♥ strt♦♥ ♥t♦♥s ♥♥♥
♦r♥ ♦ ttsts
❲♥ ❲ trt t ♥r ♠① ♠♦s ♦r rrr② ♦sr ♠t♣r♣t ♠srs t ♠ss♥ ♦t♦♠s ♦♠tr ♦r♥
❲♥ ❲ ♥ ♥ s ♠①♠♠ ♦♦ ♥r♥ ♦r ♠trt ♥r ♠① ♠♦s t t♦rrss rr♦rs ♦♠♣tt♦♥ ttsts ♥ t
♥②ss
❲♥ ❲ ♥ ♥ st♠t♦♥ ♥ ♠trt t ♥r ♠① ♠♦s ♦r♠t♣ ♦♥t♥ t ttst ♥
❲♥ ❲ ♥ ♥ ②s♥ ♥②ss ♦ ♠trt t ♥r ♠①♠♦s s♥ ♦♠♥t♦♥ ♦ ♥ s s♠♣rs ♦r♥ ♦ trt ♥②
ss
❩♥ r ♦♠♣♠♥t ♥ ts ♣♣t♦♥s ♠r t♦s ♥♦rt♠s ♣r♥r
❩♦r③♦ ♥ ♦ss ♠♣♠♥tt♦♥ ♦ t ♦♦ ♣ss♣♦rt ①♣r♥♦ t ♥tr♥t♦♥ ②♥ ♥♦♥ r st♥ ♥ ♥②ss
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r tr rs ♦ ♥trst r ♣♦tt ♦r t ♦ tst ♥ t ♥ t♥ ♦ s rr♥ ♥trs ♥ ♦tts ♥s r r t♥ t ♥♦♥s ♥ s ♥s ♣rt♦♥ r♦♥ s♥ t st♥r χ2 trs♦ x4
0.95,ξ,ξs ♦s
t♦ t♦s ♦t♥ s♥ x30.95,ξ0,ξ,W
s r ♣♣rs ♥ ♦♦r ♥ t tr♦♥ rs♦♥ ♦
ts rt
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7 8 9 10 11
Distribution of thetargeted quantileDistribution of x1
Distribution of x2
Distribution of x3
x4
r strt♦♥s ♦ t trt q♥t ♥ ♦ t r♥t ♦rrt♦♥s r r♣rs♥ts♥ r♥ st♠t xl st♥♥ ♦r xl
0.95,ξ0,ξ,W♦r l = 1, 2, 3 ♥ x4 ♦r x4
0.95,ξ,ξ
s♦ ♥ strt♦♥ s♦s ♦ t t q♥t ♥s t W strt♦♥ ♦x30.95,ξ0,ξ,W
s t ♦sst t♦ t t strt♦♥ r ♠t♦s ♥ ♦rst♠t
t t q♥ts ♠t♦ ♥rst♠ts t♠ s r ♣♣rs ♥ ♦♦r ♥ ttr♦♥ rs♦♥ ♦ ts rt