of 163
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k
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j, j = 1, . . . , p
XRnp
Xj, j = 1, . . . , p j x
Tj j
X j Xj Xj, j= 1, . . . , p
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A Rnn A
0
A> 0
i
j
A A{i,j} A{j} j A {0}
0 Rp1
j, j= 1, . . . , p
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yi= 0+1xi,1+. . .+pxi,p+i, i= 1, . . . , n, n N,
0, 1, . . . , p
R
yi
xi,j, j= 1, . . . p p
i E(i) = 0
y= X + ,
y, Rn1
X :=
1n X1 . . . X p
Rn(p+1)
1n := [1]1in X
Xj := [xi,j]1in, j= 1, . . . , p
X
X
XTX
p+ 1
n p + 1
i
2In N(0, 2In)
2
XTX
RSS() :=n
i=1
yi xTi
2= (y X)T (y X)=yTy + TXTX 2TXTy
xTi , i= 1, . . . , n i X
RSS()
= 2XTX
2XTy.
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XT
X = XT
y
:=
XTX1
XTy,
XTX
E() =
() =2
XTX
1
var(j) var(j), j= 0, 1, . . . , p
E
RSS()
= (n p 1)2,
RSS() =
ni=1(yi xTi )2
2
2 = RSS()
n p 1.
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2
:= y X
E() = 0
() =2
In X(XTX)1XT
.
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b R(p+1)1
y
b= C y + d.
C R(p+1)n d R(p+1)1
C=
XTX1
XT
d= 0.
b
d= 0
b
Bias(b) = E(b) = CE(y) + d = C X + d
(b) =C(y)CT =2CCT.
RSS
b
L(b) = (b )T W(b ) ,
W (p+ 1)(p+ 1)
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W (p + 1) (p + 1)
b
R(b) = E
(b )TW(b ) .
W = I(p+1)
b R(p+1)1
MSE(b) := E
(b )T(b )= E
(b E(b) + E(b) )T(b E(b) + E(b) )
= E
(b E(b))T(b E(b)) + (E(b) )T(E(b) )= tr((b)) + Bias(b)TBias(b),
tr
v v2 =
vTv MSE(b)
b
b
WMSE(b)
w R(p+1)1 MSE
wTb
= E
(wTb wT)T(wTb wT)
= E
(b )TwwT(b ) .
wTb
WMSE(b)
W =wwT
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(p+ 1) (p+ 1)
MtxMSE(b) := E (b )(b )T .
MtxMSE(b) = E
(b E(b) + E(b) )(b E(b) + E(b) )T= E
(b E(b))(b E(b))T + (E(b) )(E(b) )T
= (b) + Bias(b)Bias(b)T.
tr(MtxMSE(b)) = MSE(b) = E (b )T(b )
w R(p+1)1 wT(MtxMSE(b))w= tr
wTE
(b )(b )Tw
= E
tr
wT(b )(b )Tw= E
tr
(b )TwwT(b ) .
wT(MtxMSE(b))w 0
W =wwT
MSE
wTb 0
b1 b2
= MtxMSE(b2) MtxMSE(b1).
W
WMSE(b2) WMSE(b1) 0
W R(p+1)(p+1)
>
b1 b2
:= MSE(b2) MSE(b1) 0,
b1
b2 0
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bi= Ciy, i= 1, 2
= (b2) (b1) + Bias(b2)BiasT(b2) Bias(b1)BiasT(b1)=2S Bias(b1)BiasT(b1) + Bias(b2)BiasT(b2),
S= C2C
T2 C1CT1
2S Bias(b1)BiasT(b1)
Bias(b2)BiasT(b2)
A
(p + 1) (p + 1)
a
(p + 1)1
d
dAaaT
aTA1a d
dA aaT
Bias(bi) = (CiX Ip+1), i= 1, 2.
bi= Ciy, i= 1, 2
S
T(C1X Ip+1)TS1(C1X Ip+1)< 2.
= MtxMSE(b2) MtxMSE(b1)> 0,
S= C2CT2 C1CT1
opt= A0y
A0= T
XTXTXT +2In1 ,
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2
()
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yi= 0+1xi,1+. . .+pxi,p+i, i= 1, . . . , n, n p+ 1.
1
n
ni=1
yi= 0+11
n
ni=1
xi,1+. . .+p1
n
ni=1
xi,p+1
n
ni=1
i,
y = 0+1 X1+. . .+p Xp+ .
yci =1xci,1+. . .+px
ci,p+
ci , i= 1, . . . , n ,
yc =Xc{0}+ c,
T{0}:=
1, . . . , p
,
xci,j :=xi,j Xj,yci :=yi y,ci :=i , i= 1, . . . , n , j = 1, . . . , p .
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P :=In 1n 1n1Tn Rnn,
In n n 1n n 1
P
yc =P y,
c =P ,
Xc =P X{1},
X{1}:=
x1,1 . . . x1,p
xn,1 . . . xn,p
Rnp.
P
P
P2 =P
PT =P
P2 =PTP = (In 1n
1n1Tn )
T(In 1n
1n1Tn )
=In
1
n1n1
Tn
1
n1n1
Tn +
1
n21n1
Tn 1n1
Tn
=In 2n
1n1Tn +
1
n1n1
Tn
=In 1n
1n1Tn =P.
P y= y
y
y
=yc
c =P , Xc =P X{1}
P y= P X{1}{0}+ P .
RSS({0}) :=
P y P X{1}{0}T
P y P X{1}{0}
= y X{1}{0}T Py X{1}{0}
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c:=
c1, . . . ,
cp
c
=
(P X{1})TP X{1}1
(P X{1})TP y
=
(P X{1})TP X{1}1
(P X{1})T(P X{1}{0}+ P )
={0}+
(P X{1})TP X{1}1
(P X{1})TP
={0}+
XT{1}P X{1}1
XT{1}P ,
{0}=
1, . . . , p
T
E(c) ={0}+X{1}TP X{1}1 X{1}TPE() ={0}
(c) =
X{1}TP X{1}
1X{1}TP()
X{1}TP X{1}
1X{1}TP
T=2
X{1}TP X{1}
1=2
XcTXc
1.
0
c0:= y
pi=1
ci Xi= y
1
n 1Tn X{1}
c
.
y= X + ,
X=
1n X{1}
= 0
{0}
.
=
0
{0}
=
XTX1
XTy
=
1Tn 1n 1
Tn X{1}
X{1}T1n X{1}TX{1}
1 1Tn y
X{1}Ty
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= n 1Tn X{1}
X{1}T
1n X{1}T
X{1}1
1Tn y
X{1}T
y .
=
1n+
1n2
1Tn X{1}Q1X{1}T1n 1n 1Tn X{1}Q1
1n Q1X{1}T1n Q1
1Tn y
X{1}Ty
=
1n 1
Tn y +
1n2
1Tn X{1}Q1X{1}T1n1Tn y 1n 1Tn X{1}Q1X{1}Ty
1n Q1X{1}T1n1Tn y + Q1X{1}Ty
,
Q= X{1}TX{1} 1n(1Tn X{1})T(1Tn X{1})=X{1}TP X{1}=
P X{1}
TP X{1}.
{0}= 1
nQ1X{1}T1n1Tn y + Q
1X{1}Ty
= 1n
X{1}TP X{1}
1X{1}T1n1Tn y
+
X{1}TP X{1}
1
X{1}Ty
= X{1}TP X{1}1X{1}Ty 1n 1Tn X{1}T 1Tn y=
X{1}TP X{1}1
XT{1}P y
=
(P X{1})TP X{1}1
(P X{1})TP y
{0}= c.
0=
1
n1
T
n y +
1
n21
T
n X{1}Q1
X{1}T
1n
1T
n y 1
n1
T
n X{1}Q1
X{1}T
y
= y+1
n1
Tn X{1}
X{1}TP X{1}
1X{1}T1ny
1n
1Tn X{1}
X{1}TP X{1}
1X{1}Ty
= y 1n
1Tn X{1}
XT{1}P X{1}
1XT{1} (y 1ny)
= y 1n
1Tn X{1}
X{1}TP X{1}
1X{1}TP y
= y 1n
1Tn X{1}{0}
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0= c0.
XTX
y := yc
zi,j =xi,j Xj
Sjj, i= 1, . . . , n , j = 1, . . . , p
Sjj =n
i=1
(xi,j Xj)2.
yi =1zi,1+2zi,2+ +pzi,p+i , i= 1, . . . , n ,
y = Z + ,
y = P y,
Z=:
Z1 . . . Z p
= P X{1}D1,
= D{0},
= P
D=
S11
Spp
.
Zj := [zi,j]1in, j = 1, . . . , p Z
=
ZTZ
1
ZTy
= D1XT{1}P X{1}D11 D1XT{1}P y
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=D XT{1}P X{1}
1XT{1}P y= D{0}
j = j
1
Sjj
12
, j= 1, . . . , p
0 = y p
j=1
j Xj .
E() =DE({0}) =D{0}.
() =
ZTZ1
ZT(y)Z
ZTZ1
=
ZTZ1
ZTP(y)PTZ
ZTZ1
=2
ZTZ1
ZTP Z
ZTZ1
=2 ZTZ1 2
n ZTZ1
ZT1n1Tn ZZTZ1
=2
ZTZ1
,
Z ZT1n= 0 Rp1
(XTX)1
E() = 0
() =P()PT =2P,
RSS() = (y Z)T (y Z)
=
P y P X{1}{0}T
P y P X{1}{0}
= P y P X{1}{0} P 0TP y P X{1}{0} P 0
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T0 :=
0, . . . , 0 R1n
P 0= 0
RSS() =
y XT
P
y X
= TP.
E() = 0,
() =2
In X(XTX)1XT
E (RSS()) = E
TP
= ET(In 1n 1n1Tn )= E
T
1n
E
T1n1Tn
= (n p 1)2 1n
tr(1n1Tn ())
= (n p 1)2 2
ntr
1n1Tn (In X(XTX)1XT)
= (n p 2)2 +
2
n 1
Tn X(X
TX)1XT1n.
E (RSS()) = ERSS() .
2
2 = RSS()
n p 2 + 1n 1Tn X(XTX)1XT1n.
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Z1 Z2
1,2
y,i
y Zi, i= 1, 2 =
ZTZ
1ZTy
ZTZ
1=
1 1,2
1,2 1
|ZTZ| ,
|ZTZ| = 1 21,2 21,2 1 |ZTZ| 0 var(i) , i= 1, 2 cov(i, j)
1,2
1
() =2
ZTZ1
.
Z1 Z2
=
y,1 1,2y,2y,2 1,2y,1
|ZTZ
|
.
1,2 = 1 |ZTZ| = 0
1+ 2= (y,1(1 1,2) +y,2(1 1,2))|ZTZ|1 =(y,1+y,2)
(1 +1,2)
1,2= 1
1 2= (y,2 y,1)(1 1,2)
(1+ 2)
(1
2)
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p
() =2
ZTZ1
.
ZTZ = VVT
pj=1
var(j) =2tr(V1VT) =2tr(VTV
=Ip
1) =2
pj=1
1
j,
j, j = 1, . . . , p Z
TZ
Zj, j = 1, . . . , p
var(j ) =
2p
k=1
v2j,k
k ,
vj,k (j, k) V =: [vj,k]1j,kp p
p
vj,k
p
(ZTZ)1
rj,j =
1
1 R2j , j = 1, . . . , p ,
R2j
Zj (p 1)
R2j , j = 1, . . . , p
rj,j j
var(j) = 2
1 R2j, j = 1, . . . , p ,
R2j
j
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Z y y yp y = Z = Z
ZTZ
1ZTy yp= Z
ZTZ
1ZTyp Z+yp2
2 cond(ZTZ)
y yp2y2
,
Z+ :=
ZTZ1
ZT 2 y
cond(ZTZ) ZTZ
cond(ZTZ) 1
(Z+ E)+yp22
cond(ZTZ) E12
+ cond(ZTZ)2 E22y y2
y2+ cond(ZTZ)3 E222,
E
E= E1+ E2 E1
E
Z
E2
Z
cond(ZTZ)
y
Z
2 0
L2 := [ ]T [ ] .
E(L2) = MSE() =2tr(ZTZ)1 =2p
j=1
1
j
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E(T) = E yTZ(ZTZ)2ZTy= E
(Z+ )TZ(ZTZ)2ZT(Z+ )
=T+ E
TZ(ZTZ)2ZT
,
E() = 0
E(T) =T+ tr
Z(ZTZ)2ZT()
=T+2tr
(ZTZ)1
,
ZT
1n =
0
T
T
j, j = 1, . . . , p
pT
p Rp1 ZTZ p
ZTZ
pT pTp= 1
pT = V1 V1
ZTZ
pT pT = Vp
t
R2
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j
i,j, i , j= 1, . . . , p , i =j X
Xi Xj, i ,j= 1, . . . , p, i =j
i,j
i,j i,j
rj,j, j = 1, . . . , p
VIFj :=rj,j = 1
1 R2j=
var(j)2
, j = 1, . . . , p .
ZTZ rj,j = 1
VIFj, j = 1, . . . , p
j
10
ZTZ
1, . . . , p ZTZ
Z
cond(ZTZ) =max(Z
TZ)
min(ZTZ)
.
ZTZ
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cond(Z
T
Z)
ZTZ
condj(ZTZ) =
max(ZTZ)
j(ZTZ)
, j= 1, . . . , p .
ZTZ
Z
n p
Z
Z=UVT,
U Rnp, V Rpp
Rpp
k, k= 1, . . . , p
Z
Z
condk(Z) =max(Z)
k(Z) , k= 1, . . . , p .
Z
() =2V2VT
j
var(j) =2
pk=1
v2j,k2k
=2VIFj, j = 1, . . . , p .
var(j)
p
k
2k
var(1) var(2) var(p)
1 1,1 1,2 1,p2 2,1 2,2 2,p
p p,1 p,2 p,p
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k
j,k :=v2j,k2k
VIFj =
p
k=1j,k, j, k= 1, . . . , p .
j,k := j,kVIFj
.
j,k
j
k
XTX
ZTZ
ZTZ
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y
X1
X2
X3
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y= 0+1X1+2X2+3X3+
y= X +
N(0, 2I17)
T
:=
0, 1, 2, 3
T :=
0, 1, 2, 3
R2 p t
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y
X1
1
X
10
X
X
XTX
XTX
X
max
XTX j, j = 2, 3
X
cond(X) = maxmin = 3.936520.00003568 = 332.15196,
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95
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r
(ZTZ+kIp)r = ZTy,
r = (ZTZ+kIp)1ZTy,
k >0
k= 0
r =
ZTZ+kIp1
ZTy
=
ZTZ+kIp1
ZTZ
ZTZ1
ZTy
=
ZTZ+kIp
1
ZTZ
= Ip+k(ZTZ)11 =Kr,
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Kr :=
Ip+k(ZTZ)1
1
=Ip k ZTZ+kIp
1
E(r) = E(Kr
) = Kr
r
Bias(r) = E(r) = (Kr Ip) = k ZTZ+kIp1
BiasT(r)Bias(r) =k2T
ZTZ+kIp
2.
r
(r) = (ZTZ+kIp)
1ZT(y)Z(ZTZ+kIp)1
= (ZTZ+kIp)1ZT()Z(ZTZ+kIp)1
= (ZTZ+kIp)1ZTP()PTZ(ZTZ+kIp)1
=2(ZTZ+kIp)1ZT
In 1
n1n1
Tn
Z(ZTZ+kIp)
1
=2(ZTZ+kIp)1ZTZ(ZTZ+kIp)1
=2Kr(ZTZ+kIp)
1 =:2KrZr,
ZT1n Z j, j =
1, . . . , p ZTZ
ZTZ=VVT
=
1
p
VTV =Ip.
Vj V j, j = 1, . . . , p
ZTZ
(ZTZ)1 =V1VT.
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(ZTZ)1 ZTZ 1j
Vj, j= 1, . . . , p
j Z
TZ
Vj , j= 1, . . . , p
Zr = (Z
TZ+kIp)1
j =
1j+k
Vj
Kr =
k(ZTZ)1 + Ip
1
j = jj+k
Vj
j = 1, . . . , p
j Z
TZ
Vj
ZTZVj =jVj, j= 1, . . . , p .
ZTZ+kIp
Vj = (j+k) Vj , j= 1, . . . , p .
(ZTZ+ kIp) j+ k Vj
(ZTZ+ kIp) k >0
Kr
j := 1j+k
Vj
(ZTZ)1
1j
Vj, j = 1, . . . , p
(ZTZ)1Vj = 1
jVj
k(ZTZ)1Vj = kj
Vj
k(ZTZ)1 + IpVj = kj
+ 1
Vj, j = 1, . . . , p .
Kr j = kj + 11 = jj+k
Vj
pj=1
var(rj ) =2tr
V
1
p
VTV
1
p
VT
=2tr1
p 1
p = 2
p
j=1j
(j+ k)2
.
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r
k
r
MSE(r) =
pj=1
var(rj ) + biasT(r)bias(r)
=2p
j=1
j(j+k)2
+k2T(ZTZ+kI)2.
r
k
k
r
k >0
MSE(r)< MSE().
r
RSS(r) = (y Zr)T (y Zr)
= ((y Z) + (Z Zr))T ((y Z) + (Z Zr))= (y Z)T(y Z) + 2(y Z)T (Z Zr)
+ ( r)TZTZ( r)= (y Z)T(y Z) + ( r)TZTZ( r)= RSS() + ( r)TZTZ( r),
Z= ZZTZ1 ZTy 2(y Z)T (Z Zr) = 2yT
In Z
ZTZ
1ZT
Z( r) = 0.
X
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g
RSS(g) = (y Zg)T(y Zg)= (y Z)T(y Z) + (g )TZTZ(g )= RSS() +(g).
RSS(g)
RSS(g) RSS()
(g ) g0
RSS(g0
) = RSS() +0
0
> 0
ZTZ
ZTZ
min gTg
(g )TZTZ(g ) =0.
F :=gTg +1
k
(g )TZTZ(g ) 0
,
1k
F
g = 2g +
1
k
2ZTZg 2ZTZ= 0.
r :=
Ip+
1
kZTZ
1 1k
ZTZ
=
ZTZ+kIp1
ZTy,
k
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r
k
k
k
k
r k k (0, 1]
k
k
r
k
r
k
k
k
k
k= p2
T,
2 2
k= p2
T ZTZ= Ip
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K
N(0, 2In) E (RSS()) =2(n p).
2 = RSS(
)np
2
k
k
k0
ki= p2p
j=1(j(ki1))2, i 1,
ki k
Q
Q:= T 2p
j=1
1j
,
j Z
TZ
k
r(k)Tr(k) =Q,
Q> 0
k= 0
k=
k
r k
k
E(T) =T+2tr
(ZTZ)1
.
k
T
E(r(k)Tr(k)) = E(
T) 2p
j=1
1
j
=T.
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Q
k= 0
k=
k
r(k)Tr(k) = abs(Q)
abs(Q)
Q
y= X + ,
N(0, 2
In)
2 =RSS()
n p
2
k
k
1.0
10
kI
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k
k
k
k
k
ZTZ
ZTZ
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ZTZ
kIp X
TX R(p+1)(p+1) X
bTb
min bTHb,
b
(b )TXTX(b ) =0.
H
R(p+1)(p+1)
Fg := bTHb +
1
k
(b )TXTX(b ) 0
.
XTX
g =
XTX+kH1
XTy.
H=Ip+1
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H = 1k G G R(p+1)(p+1)
g =
XTX+ G1
XTy.
XTX = VVT
V
H = 1k V KV
T
K
g = XTX+ V KVT1 XTy.
H=XTX
g =
(1 +k)XTX1
XTy
= 1
1 +k= , [0, 1].
s := 1 c2
T
Z
T
Z ,
c > 0
c R
2
k
(g) =
2 XTX+kH1 XTX XTX+kH1
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Bias(g) = E(g) = XTX+kH1 XTX =
XTX+kH1
XTX Ip.
XTX+kH
1 XTX
Ip= XTX+kH1 kH
MtxMSE(g) =
XTX+kH1
k2HTH+2XTX
XTX+kH1
.
g
:= MtxMSE() MtxMSE(g)
T2
kH1 + (XTX)11 2,
H
=2
XTX1 XTX+kH1 k2HTH
+2XTX
XTX+kH
1 0.
= UT
U
U
p H
XTX+kH
pT
XTX+kH
XTX+kH
p
=pT
XTX+kH
UTU
XTX+kH
p
=pT
U
XTX+kHT
U
XTX+kH
p 0, p
R(p+1)1
(XTX+ kH)
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2 XTX+kH XTX1 XTX+kH k2HTH 2XTX 0.
2
XTX+kH
XTX1
XTX+kH
=2
XTX+ 2kH+k2H
XTX1
H
2 2kH+k2HX
TX1
H k2HTH 0.
1k H
1
2
2
kH1 +
XTX
1 T 0.
pTg, p R(p+1)1
T
2
kIp+
XTX
1 2,
T2G1 + XTX1 2
G
T
2K1 +
XTX1
2,
T
XTX
k+ 2k
2.
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bg =
XTX+ C+
XTy,
XTX+ C
+
XTX+ C+
C
XTX
C
Z
Z= UVT.
=
ZTZ
1
ZTy= V1VTV12 UTy
=V
12
UT
y,
ZTZ
r =V 1
2 UTy,
1, . . . , p R
W
j = jj+k
, j = 1, . . . , p
B
B
W
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k
N(0, 2I17)
2
2 = RSS()
n
p
1
= 11.369
17
3
1
= 0.87453.
r
k
r =
ZTZ+kI31
ZTy.
r{0}
T :=
r1, r2,
r3
{0}T =
1, 2, 3
k
r{0}= D
1r = D1 ZTZ+kI31 ZTy,
D
r0 = y
3
j=1 r
jXj .
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k
k
k
0.05
k
k
k
10
k 0.05
k
y = Z +
T = 19.106, 24.356, 6.4207 .
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k
k
k = 42ZT
2Z=RSS()
n p =11.368
14 = 0.8120,
2
RSS()
k= 0.00325.
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k
r
(k) =3.3497, 0.3787, 1.5042, 7.8142 104
T.
k
r(k)Tr(k) T 2tr
(ZTZ)1
.
2Z
2
QZ := T
2Ztr (ZTZ)1= 138.0
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kZ= 0.0033.
r
(k) =3.3781, 0.3642, 1.4962, 7.80 104
T.
k
2
2 = RSS()1731 = 0.87453
k
MSEk(r) = 2
pj=1
j(j+ k)2
+k2T(ZTZ+kI)2.
r
k
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kmin= 0.0012
kmin
MSE(kmin) = 517.06.
kmin= 0.0012
r
(k) =0.7410, 1.6031, 2.0893, 0.0012
T.
k
k
k
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j
Zj, j = 1, . . . , p
Z
n p
n > p
Zj, j = 1, . . . , p
min
ni=1
(yi zTi T)2,
zTi i Z
T =
1, . . . , p
= 0
R
min (y (Z+
))
T
(y (Z+
)) ,
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:=
1 . . . p
1 . . . p
Rnp, n > p.
(Z+)T (Z+) = (Z+)T y.
y
ni=1y
i = 0
Ty = 1
ni=1y
i
pn
i=1yi
= 0 Rp1.
Z
TZ=ZT= 0.
M= [mu,v]1u,vp :=
Z+T
Z+
= ZTZ+2T.
M ZTZ
T
pTMp= pT
ZTZ
p +2pT
T
p> 0
p Rp1
=
(Z+)T (Z+)1
(Z+)T y
=
ZTZ+2T1
ZTy.
2T
M
M{u,v} (p 1) (p 1)
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M u v
M{u,v}=
m1,1 . . . m1,v1 m1,v+1 . . . m1,p
mu1,1 . . . mu1,v1 mu1,v+1 . . . mu1,pmu+1,1 . . . mu+1,v1 mu+1,v+1 . . . mu+1,p
mp,1 . . . mp,v1 mp,v+1 . . . mp,p
, u , v= 1, . . . , p .
M
M1 =M
|M
|,
M:= [mu,v]1u,vp Rpp M mu,v := (1)u+v
M{v,u} .
M1x :=(X+)T(X+)
1 X Rnp
X
n p
n p
n p
n p j , j = 1, . . . , p Mx = (X+)
T(X+)
|Mx| =2TAx + 2bxT + |XTX|,
T :=
1, . . . , p
,
bxT :=
|XTX[1]|, . . . , |XTX[p]|
Ax:=
|X[1]TX[1]| . . . |X[1]TX[p]|
|X[p]TX[1]| . . . |X[p]TX[p]|
,
X[j], j = 1, . . . , p n p X j
X
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|Mx| =
1j1...jpn
(X+)T
1 . . . p
j1 . . . jp
2
=
1j1...jpn
XT
1 . . . p
j1 . . . jp
+T
1 . . . p
j1 . . . jp
2
.
p p
XT
1 . . . p
j1 . . . jp
T
1 . . . p
j1 . . . jp
s=
n
p
{j1, . . . , jp} 1j1 . . .jp n p {1, . . . , n} {j1,k, . . . , jp,k}, k= 1, . . . , s
XT k :=XT
1 . . . p
j1,k . . . jp,k
T k := T
1 . . . p
j1,k . . . jp,k
k
{j1,k, . . . , jp,k
}
{1, . . . , n
}
XT k +T k , k = 1, . . . , s
{i1, . . . , ir} {1, . . . , n} |C{i1,...,ir}p |k p p i1, . . . , ir i1, . . . , ir
T k XT k
k = 1, . . . , s
r 2 C{i1,...,ir}p
T k |C{i1,...,ir}p |k = 0, r 2 r= 1 ir =r
C{r}p k =r|X[r]T
k
|,
X[r]
T k
XT k
r
XT k
|C{}p|k =|XT k |
XT k +T k= {i1,...,ir}
C{i1,...,ir}p k
= |XT k | +p
r=1
C{r}p k
= |XT k | +1|X[1]T k | +. . .+p|X[p]T k |, X[j]
T k , j = 1, . . . , p XT k
j
XT
k
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|Mx| =s
k=1
|XT k | +
pr=1
C{r}p k
2
=s
k=1
|XT k |2 + 2|XT k |
pr=1
r|X[r]T k |
+2p
t=1
pr=1
rt|X[r]T k ||X[t]T k |
=s
k=1|XT k |2 + 2
p
r=1r
s
k=1|XT k ||X[r]T k |
+2p
t=1
pr=1
rt
sk=1
|X[r]T k ||X[t]T k |.
|XTX| =s
k=1
|XT k |2,
|XTX[r]| =s
k=1
|XT k ||X[r]T k |,
|X[r]TX[t]| =s
k=1
|X[r]T k ||X[t]T k |
|Mx| =2p
t=1
pr=1
rt|X[r]TX[t]| + 2p
r=1
r|XTX[r]| + |XTX|.
|Mx| =2TAx + 2bxT + |XTX|.
ARpn B Rnp np
|AB
|=
1j1...jpn A1 . . . p
j1 . . . jp B j1 . . . jp
1 . . . p
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|Mx
|=
3
k=1 |XT
k
+T
k
|2
=
XT
1 2
1 2
+T
1 2
1 2
2
+
XT
1 2
1 3
+T
1 2
1 3
2
+
XT
1 2
2 3
+T
1 2
2 3
2
=
1 21 5
+
1 1
0 0
2
+
1 21 3
+
1 1
0 0
2
+ 2 25 3 + 1 10 0 2
XT k +T k= {i1,...,ir}
C{i1,...,ir}p k
,
{1, 2} {}
{1}
,{
2}{1, 2}.
C{i1,...,ir}p 2 2 i1, . . . , ir i1, . . . , ir
T k
XT k
1 21 5
+
1 1
0 0
=1 21 5
+
1 1
1 5
+ 1 20 0 +
1 1
0 0
1 21 5
+
1 1
0 0
=1 21 5
+1
1 1
1 5
1 21 3
+
1 1
0 0
=
1 21 3
+1
1 1
1 3
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2 2
5 3 + 1 1
0 0 = 2 2
5 3+1 1 1
5 3
|Mx| =1 21 5
+1
1 1
1 5
2
+
1 21 3
+1
1 1
1 3
2
+
2 2
5 3
+1
1 1
5 3
2
.
X[1]
XTX[1] =1 2 2
1 5 3
1 11 51 3
X[1]TX[1] =
1 1 1
1 5 3
1 11 51 3
.
|XTX| = 1 21 52
+ 1 21 32
+ 2 25 32
,
|XTX[1]| =1 21 5
1 1
1 5
+1 21 3
1 1
1 3
+
2 2
5 3
1 1
5 3
,|X[1]TX[1]| =
1 1
1 5
2
+
1 1
1 3
2
+
1 1
5 3
2
|Mx
|=221
|X[1]
TX[1]|
+ 21|XTX[1]
|+
|XTX
|.
Mx i= 0, 1 i q
1 qp
i= 0, i > q
TAx=
qs=1
qr=1
rs|X[r]TX[s]| =Tq Aqxq,
bTx =
q
r=1 r|XTX[r]
|=bqx
Tq
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Tq :=1, . . . , q ,
bqxT :=
|XTX[1]|, . . . , |XTX[q]|
,
Aqx:=
|X[1]TX[1]| . . . |X[1]TX[q]|
|X[q]TX[1]| . . . |X[q]TX[q]|
.
|Mx|
2Tq Aqxq+ 2b
qx
T + |XTX| = 0.
1, 2
1/2=2bqxTq
4
(bqxTq)
2 Tq Aqxq|XTX|
2Tq Aqxq
D:= 4
(bqxTq)
2 Tq Aqxq|XTX|
.
|Mx|
Aqx
Ru, u= 1, . . . , m n p n p
R=
|RT1 R1| |RT1 R2| . . . |RT1 Rm||RT2 R1| |RT2 R2| . . . |RT2 Rm|
|RTmR1| |RTmR2| . . . |RTmRm|
R= RT
R,
RT
:=
RT11 . . . RT1s
RTm 1 . . . RTm s Rms
s=
n
p R
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|RTu Rv| =|RTv Ru|, u , v = 1, . . . , m
|RTu Ru| =
1j1...jpn
RTu
1 . . . p
j1 . . . jp
2
=s
k=1
RTuk2 , u= 1, . . . , m
|RTu Rv| =
1j1...jpn
RTu
1 . . . p
j1 . . . jp
RTv
1 . . . p
j1 . . . jp
=
s
k=1 RTuk
RTvk
u, v= 1, . . . , m , u =v.
s =
n
p
{j1,k, . . . , jp,k}, k = 1, . . . , s {1, . . . , n}
R= RT
R R
R
Aq
x= A
TA
AT
=
X[1]T 1 . . . X[1]T s
X[q]T 1 . . . X[q]T s Rqs,
Aqx
Tq A
qxq 0 Tq Aqxq > 0 |Mx|
Aqx bqx |XTX| = 0
B:= Aqx bqxb
qx
T
|XTX|
B 0
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G:=
Aqx b
qx
bqxT |XTX|
=
|X[1]TX[1]| . . . |X[1]TX[q]|
|X[q]TX[1]| . . . |X[q]TX[q]|
|XTX[1]|
|XTX[q]|
|XTX[1]| . . . |XTX[q]| |XTX|
,
R(q+1)(q+1).
|XTX
|=
1j1...jpn XT 1 . . . pj1 . . . jp
2
=s
k=1
XT k2
=XTX
,
XT :=
XT 1 , . . . , XT s R1s.
AT
X
=
X[1]T 1 . . . X[1]T s
X[q]T 1 . . . X[q]
T s
XT 1
XT s
=
|X[1]TX|
|X[q]TX|
=|XTX[1]|
|XTX[q]|
=bqx,
sk=1
X[i]T k XT k= |X[i]TX|, i= 1, . . . , q ,
G= AT
A AT
X
XTA X
TX= A
T
XT A X R(q+1)(q+1)
G
Aqx
bqxbqx
T
|XTX|
0.
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0 Tq
Aqx bqxbqxT|XTX|
q =Tq A
qxq (Tq bqx)(bqxTq)|XTX|
=Tq Aqxq
(Tq bqx)
2
|XTX| bqxT2 TAqx|XTX| 0,
D
|Mx|
|Mx| = 0 |Mx|
s=
n
p
=
n!
(n p)!p! =n(n 1) (n 2) . . . (p+ 1)
p (p 1) . . . 2 1 n, p < n
G
A X
Rs(q+1), qp
rank
A X
= q+ 1
G
q= p = n
s = 1
rank
A X
= 1
X
X
= 0
rank A X< q+ 1
j
X
c R
X
j
A
rank
A X
< q+ 1
G
G |Mx|
|Mx| |Mx| >0
Mx
|Mx| 0 Mx (X+ )
p
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X np np
n p
j, j = 1, . . . , p
Mx=
X+T
X+
M1x =Mx
|Mx| = 2 M
quadx + M
linx + M
constx
2TAx + 2bTx + |XTX|
,
Mquadx :=
mquadx u,v
1u,vp
=
(1)u+v{u}TA
(uv)x {v}
1u,vp
,
M
lin
x := mlinx u,v1u,vp = (1)u+v b(uv)x T{v}+ b(vu)x T{u}1u,vp ,
Mconstx :=
mconstx u,v
1u,vp=
(1)u+v X{u}TX{v}
1u,vp
{u}:=
r
1rpr=u
R(p1)1,
b(uv)x :=
X{u}TX{v}[r]
1rpr=v R(p1)1,
A(uv)x :=
X{u}[r]TX{v}[s] 1r,spu=r;v=s
R(p1)(p1).
X{u} Rn(p1) u X X{u}[r]
X
r
X
u
Mx =:
mxu,v
1u,vp Mx
X{u}, {u} X{v}, {v} n (p 1)
X
u
v
mxv,u = mxu,v = (1)u+v
X{u}+{u}TX{v}+{v}= (1)u+v
sk=1
X{u}T k +{u}T k X{v}T k +{v}T k ,
s :=
n
p 1
(p 1)
{1, . . . , n}
k
k= 1, . . . , s
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X{u}T k +{u}T k
:=
X{u}T 1 . . . p 1j1,k . . . jp1,k +{u}T 1 . . . p 1j1,k . . . jp1,k .
X{u}T k +{u}T k= |X{u}T k | + pr=1
r=u
r|X{u}[r]T k |
X{v}T
k
+
{v
}
T
k
= |X{v}T
k
|+
p
s=1s=v
s
|X
{v
}[s]
T
k
|,
X{u}[r], r = 1, . . . , p, r=u X{u}
r X X{u}
mxu,v = (1)u+vs
k=1
|X{u}T k ||X{v}T k |
+
p
s=1s=vs|X{u}T k ||X{v}[s]T k | +
p
r=1r=ur|X{v}T k ||X{u}[r]T k |
+2ps=1
s=v
pr=1
r=u
rs|X{u}[r]T k ||X{v}[s]T k |
= (1)u+v2 p
s=1s=v
pr=1r=u
rs|X{u}[r]TX{v}[s]| +ps=1s=v
s|X{u}TX{v}[s]|
+
p
r=1r=ur|X{v}TX{u}[r]| + |X{u}TX{v}|
=2mquadx u,v+mlinx u,v+ m
constx u,v
Mquadx
Mlinx
Mconstx p p
Mconstx X
TX
= 0
XTX
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|Mx|
Mx
Z Rnp, n > p
M =
Z+T
Z+
= ZTZ+2T,
Z
ZTZ[v] =
Z12 . . . Z 1TZv1 0 Z1TZv+1 . . . Z 1TZp
ZpTZ1 . . . Z pTZv1 0 ZpTZv+1 . . . Zp2
|ZTZ[v]| = 0, v= 1, . . . , p
bx= 0
Z[u]TZ[v] =
Z12 . . . Z 1TZv1 0 Z1TZv+1 . . . Z 1TZp
Zu1TZ1. . . Z u1TZv1 0Zu1TZv+1. . . Z u1TZp0 . . . 0 n 0 . . . 0
Zu+1TZ1. . . Z u+1
TZv1 0Zu+1TZv+1. . . Z u+1TZp
ZpTZ1 . . . Z p
TZv1 0 ZpTZv+1 . . . Zp2
|Z[u]TZ[v]| = (1)u+vn|Z{u}TZ{v}|, p 2, u , v= 1, . . . , p .
Z
Ax
n
|ZTZ|
Ax = n
(1)u+v Z{u}TZ{v}
1u,vp
r =u
s =v|Z{u}TZ{v}[s]| = 0
|Z{u}[r]T
Z{v}[s]| = (1)r+s
n|Z{ur}T
Z{vs}|, p 3,
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Z{ur}, r = 1, . . . , p u r Z
Z{1}[2]= Z{2}[1] = 1n
p= 2
|Z{u}[r]TZ{v}[s]| =n, u, v , r, s = 1, 2; r =u; s =v.
b(uv)x = 0
A(uv)x = n , p= 2
(1)r+sn|Z{ur}TZ{vs}|1r,spu=r;v=s
, p 3.
(5) mu,v = (1)u+vn2 p
r=1r=u
ps=1s=v
(1)r+srs|Z{ur}TZ{vs}| + |Z{u}TZ{v}|
,
1 u, vp, p 3
p= 2
mu,v = (1)u+vn2 2
r=1
r=u
2s=1
s=v
rs+ |Z{u}TZ{v}|
, u, v= 1, 2.
Z
Z
n p
n > p, p 2
np
j, j = 1, . . . , p M =
(Z+)T(Z+) =ZTZ+2T
M1 =M
|M| = n2 M
quad+ M
const
n2T Mconst
+ |ZTZ|,
Mquad
:=
mquadu,v
1u,vp
:=
(1)u+v{u}TA
(uv){v}
1u,vp
,
Mconst
:= mconstu,v 1u,vp:= (1)u+v Z{u}
TZ
{v
}1u,vp ,
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{u}:= r 1rpr=u
R(p1)1,
A(uv)
:=
1 , p= 2(1)r+s|Z{ur}TZ{vs}|
1r,spu=r;v=s
, p 3 R(p1)(p1).
Mconst
ZTZ
Mconst
=
|ZTZ
| ZTZ
1
Rpp.
ZTZ
ZTZ |ZTZ| >0
Mconst
n2T M
const 0 |ZTZ| >0 Z
|M| >0
M
Z
ZT =
2 1 12 2 0
,
X
T =
1 1 1
0 0 0
.
ZTZ= 6 66 8
=
1 0
.
A(11)
= A(12)
= A(21)
= A(22)
= 1,
{1}= 0,
{2}= 1
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Mquad=0 0
0 21
,
Mconst
=
8 66 6
M1 =
n2
0 0
0 21
+
8 66 6
n2218 + 6 66 8
= 1
24221+ 12
3221
0 0
0 1
+
8 66 6
.
|M|
M
M1
= (ZTZ+2T)1ZTy
= n2 M
quad+ M
const
n2T Mconst
+ |ZTZ|ZTy,
Mquad
=
mquadu,v
1u,vp
=
(1)u+v{u}TA
(uv){v}
1u,vp
,
Mconst =
mconstu,v
1u,vp =
(1)u+v Z{u}TZ{v}
1u,vp.
= 0
0=M
const
|ZTZ| ZTy= .
Z
y=
10
1
.
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= 1
24221+ 12
3221
0 0
0 1
+
8 66 6
2 1 12 2 0
101
= 1
2221+ 1
1
0.5(221 1)
.
= 0
= 1
0.5 .
1= 1
0 1 2 3 4 5
0.5
0
0.5
1
1
2
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=:
1 . . .
p
T
() = (ZTZ+2T)1ZT(y)Z(ZTZ+2T)1
= (ZTZ+2T)1ZT()Z(ZTZ+2T)1
= (ZTZ+2T)1ZTP()PTZ(ZTZ+2T)1
=2(ZTZ+2T)1ZT
In 1n
1n1Tn
Z(ZTZ+2T)1
=2(ZTZ+2T)1ZTZ(ZTZ+2T)1,
ZT1n Z
() =2(ZTZ+2T)1(ZTZ+2T2T)(ZTZ+2T)1
=2(ZTZ+2T)1 22(ZTZ+2T)1T(ZTZ+2T)1
=2 n2 M
quad+ M
const
n2T Mconst
+ |ZTZ|
22 n2 M
quad+ M
const
n2
T
M
const
+ |ZT
Z|
T
n2 Mquad
+ Mconst
n2
T
M
const
+ |ZT
Z|.
A Rp(p+1)A{r}[l]= (1)(lr+1) A{l}[r] , 1 r, l p, l =r, A{r}[l] A l
r
A{r}[l] A{l}[r]
l > r
A{r}[l] A{l}[r] r
(r+ 1)
(r+ 1)
(r + 2)
(l 1)
A{l}[r]
= l 2 l 1 . . .r+ 1 r+ 2r r+ 1 .
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sign() = (1)(l1)r = (1)lr+1.
sign()
A{r}[l]= (1)(lr+1) A{l}[r] , 1 r < l p.
l
r
l < r A{l}[r]= (1)(rl+1) A{r}[l]
A{r}[l]= (1)(lr+1) A{l}[r] .
Mquadx
Mquadx = 0.
(u, v)
M
quadx Rnp
u
Mquadx (u, v) =
pl=1
(1)l+vl{l}TA(lv)x {v},
A(lv)x =|X{l}[r]TX{v}[s]|
1r,spl=r;v=s
Mquadx (u, v) =
pl=1
ps=1
s=v
pr=1
r=l
(1)l+vrslX{l}[r]TX{v}[s]
=
ps=1s=v
pl=2
l1r=1
(1)l+vrlX{l}[r]TX{v}[s]
+
p
r=2
r1
l=1
(
1)l+vr
l X{l}[r]TX{v}[s]s
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=
p
s=1s=v
p
l=2l1
r=1(1)l+vrl X{l}[r]TX{v}[s]
+
pl=2
l1r=1
(1)r+vrlX{r}[l]TX{v}[s]
s.
s=
n
p 1
X{r}[l]TX{v}[s]
=
sk=1
X{r}[l]T k
X{v}[s]T k
= (1)lr+1
sk=1
X{l}[r]T k X{v}[s]T k= (1)lr+1 X{l}[r]TX{v}[s] .
M
quadx n p
Z
M
quad
Mquad
= 0
Rnp
() =2 n
2 Mquad
+ Mconst
n2T Mconst
+ |ZTZ|
22
(n2T Mconst
+ |ZTZ|)2M
const
T M
const.
Mconst
T
Mconst
=
n
ps=1
pr=1
(1)u+v+r+srs|Z{u}TZ{r}||Z{v}TZ{s}|1u,vp
M
const
T M
const
tr
Mconst
T
Mconst
= n
pj=1
pr=1
(1)rr|Z{j}TZ{r}|2
.
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cov(u , v) =
2 n2mquadu,v + mconstu,v
n2T Mconst
+ |ZTZ|
22n
ps=1
pr=1(1)u+v+r+srs|Z{u}TZ{r}||Z{v}TZ{s}|(n2T M
const + |ZTZ|)2
, u, v= 1, . . . , p ,
mquadu,v mconstu,v
tr(()) =
p
j=1
var(
j)
=2p
j=1
n2{j}TA(jj){j}+ |Z{j}TZ{j}|
n2T Mconst
+ |ZTZ|
n2p
r=1(1)rr|Z{j}TZ{r}|2
(n2T Mconst
+ |ZTZ|)2
.
2 1.5 1 0.5 0 0.5 1 1.5 20
0.1
0.2
0.3
0.4
0.5
0.6
var(1
)/
2
var(2
)/
2
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() =2 n
2 Mquad + Mconst
n2T Mconst
+ |ZTZ|
22
(n2T Mconst
+ |ZTZ|)2M
const
T M
const
= 2
24221+ 12
8 66 6 + 3221
2221(24221+ 12)
2
192 144144 108
=2
23
(2221+1)2
12
(2221+1)2
12
(2221
+1)2
12(441+
221+1)
(2221
+1)2
.
var(1) 1
1 :=
var(1)
var(1)
=
163(22 + 1)3
var(1) = 0 = 0
1
1
1/
2
2/2
1= 1
Bias() = E() =
ZTZ+2T1
ZTE(y) = ZTZ+2T
1ZT (Z+ E())
=
ZTZ+2T1
ZT (Z+ PE()) =
ZTZ+2T1
ZTZ =
ZTZ+2T1
ZTZ+2T 2T = 2(ZTZ+2T)1T
= 2 MT
n2T Mconst
+ |ZTZ|
=
2 M
const
T
n2T Mconst
+ |ZTZ| Rp1,
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BiasT()Bias() = 4TT( M
const)2T
(n2T Mconst
+ |ZTZ|)2 R.
Bias() = 2 M
const
T
n2T Mconst
+
|ZTZ
|
=
2
8 66 6
1 1 1
0 0 0
1 01 01 0
24221+ 12
.
=
1 1
T
Bias() =
2
2221+12(2+7221)2(2221+1)
.
2 1.5 1 0.5 0 0.5 1 1.5 20
1
2
3
4
5
6
7
8
9
10
Bias()
TBias(
)
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BiasT()Bias() =144(8 + 28221+ 49441)
(2221+ 1)2
.
1 = 1
= 0
MSE() =
pj=1
var(j) + BiasT()Bias(),
pj=1
var(j) =2
pj=1
n2{j}TA(jj){j}+ |Z{j}TZ{j}|
n2T Mconst
+ |ZTZ|
n2p
r=1(1)rr|Z{j}TZ{r}|2
(n2T Mconst
+ |ZTZ|)2
BiasT()Bias() = 4TT( M
const)2T
(n2T Mconst
+ |ZTZ|)2,
MSE()
MSE() MSE()
MSE() =
pj=1
var
j
+
BiasT()Bias()
,
BiasT()Bias()
=
4TT( M
const)2T
(n2T Mconst
+ |ZTZ|)2
=43TT( M
const)2T(n2T M
const + |ZTZ|)
(n2T Mconst
+ |ZTZ|)3
4n5T M
constTT( M
const)2T
(n2T Mconst
+ |ZTZ|)3
= 43|ZTZ|TT( Mconst)2T
(n2T Mconst
+ |ZTZ|)3,
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pj=1
var(j) =2
pj=1
n2{j}TA(jj){j}+ |Z{j}TZ{j}|n2T M
const + |ZTZ|
n2p
r=1(1)rr|Z{j}TZ{r}|2
(n2T Mconst
+ |ZTZ|)2
=2p
j=1
2n{j}TA(jj){j}(n2T Mconst + |ZTZ|)
(n2T Mconst
+ |ZTZ|)2
2nT M
const
n2{j}TA
(jj){j}+ |Z{j}TZ{j}|(n2T Mconst + |ZTZ|)2
2np
r=1(1)rr|Z{j}TZ{r}|2
(n2T Mconst
+ |ZTZ|)(n2T M
const + |ZTZ|)3
+4n23T M
constp
r=1(1)rr|Z{j}TZ{r}|2
(n2T Mconst
+ |ZTZ|)3
=2p
j=1
2n|ZTZ|{j}TA(jj){j} 2nT Mconst|Z{j}TZ{j}|
(n2T Mconst
+ |ZTZ|)2
2n|ZTZ| 2n23T Mconst
pr=1(1)rr|Z{j}TZ{r}|2(n2T M
const + |ZTZ|)3
= 2n2p
j=1
{j}TA(jj){j}|ZTZ| T Mconst|Z{j}TZ{j}|
(n2T Mconst
+ |ZTZ|)2
|ZTZ| n2T Mconstpr=1(1)rr|Z{j}TZ{r}|2
(n2T Mconst
+ |ZTZ|)3
= 2n2p
j=1nT M
consts1(j)
3 + |ZTZ|s2(j)(n2T M
const
+ |ZTZ|)3,
s1(j) :={j}TA
(jj){j}|ZTZ| T M
const|Z{j}TZ{j}|
+
pr=1
(1)rr|Z{j}TZ{r}|2
,
s2(j) :={j}TA
(jj){j}|ZTZ| T M
const|Z{j}TZ{j}|
p
r=1
(
1)rr|Z{j}
TZ{r}|
2
.
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MSE()
= 2n2
pj=1
nT Mconsts1(j)3 + |ZTZ|s2(j)(n2T M
const + |ZTZ|)3
+43|ZTZ|TT( Mconst)2T
(n2T Mconst
+ |ZTZ|)3.
|ZTZ| >0
M
const
n2T Mconst
> 0.
MSE()
=0
= 0,
= 0
[, ]
= 0
[, 0)
(0, ]
= 0 >0 [, ]\{0} : MSE()< MSE().
= 0
= 0
= 0
= 0
= 0
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A= [ar,s]1r,sp
|A{i,j}||A{k,l}| |A{i,l}||A{j,k}| =(1)
i+j|A| p= 2|A{ik,jl}||A| p 3
, i =k, j=l,
A{q,v} R(p1)(p1), q , v = i ,j,k,l A
q
v
A{ik,jl} R(p2)(p2) i
k
j
l
p= 2
i ,j,k,l= 1, 2
i =k
j=l
i= j
k= l
i =j
k=l
(1) i = 1, j = 1, k= 2, l= 2
(2) i = 2, j = 1, k= 1, l= 2
(3) i = 1, j = 2, k= 2, l= 1
(4) i = 2, j = 2, k= 1, l= 1.
|A{1,1}||A{2,2}| |A{1,2}|2 =a1,1a2,2 a21,2= |A| = (1)i+j|A|
|A{1,2}|2 |A{1,1}||A{2,2}| =a21,2 a1,1a2,2= |A| = (1)i+j |A|.
p3
i A
(1)i1
(i 1)
i
A A
(i 1)
j
k
l
A
j
k
l
|A| =
ai,i ai,j ai,k ai,l
ai,j aj,j aj,k aj,l
ai,k aj,k ak,k ak,l
ai,l aj,l ak,l al,l
aiajakal
aTi aTj a
Tk a
Tl A{ijkl,ijkl}
,
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aq = aq,1, . . . , aq,i1, aq,i+1, . . . , aq,j1 , aq,j+1 , . . .
. . . , aq,k1, aq,k+1, . . . , aq,l1 , aq,l+1, . . . , aq,p
R1(p4), q= i,j,k,l.A{ijkl,ijkl} A i j k l
i
j
k
l
A{ijkl,ijkl}
p Rp1
i
j
k
l
pT :=p1, . . . , pi1, 0, pi+1, . . . , pj1, 0, pj+1, . . .
. . . , pk1, 0, pk+1, . . . , pl1, 0, pl+1, . . . , pp i =k, j=l.
pTAp= p{ijkl}TA{ijkl,ijkl}p{ijkl},
p{ijkl}T :=
p1, . . . , pi1, pi+1, . . . , pj1, pj+1, . . .
. . . , pk1, pk+1, . . . , pl1, pl+1, . . . , pp R1(p4).
A
pTAp > 0
p
p{ijkl}TA{ijkl,ijkl}p{ijkl}> 0 p{ijkl}
A{ijkl,ijkl}
W = [wr,s]1r,sp4 := (A{ijkl,ijkl})1.
|A| = A{ijkl,ijkl}
ai,i ai,j ai,k ai,l
ai,j aj,j aj,k aj,l
ai,k aj,k ak,k ak,l
ai,l aj,l ak,l al,l
aiajakal
W
aTi aTj aTk aTl
=: |W|1
ai,i ai,j ai,k ai,l
ai,j aj,j aj,k aj,l
ai,k aj,k ak,k ak,l
ai,l aj,l ak,l al,l
m1,1 m1,2 m1,3 m1,4
m1,2 m2,2 m2,3 m2,4
m1,3 m2,3 m3,3 m3,4
m1,4 m2,4 m3,4 m4,4
.
|A{i,j}| = (1)i+j|W|1
ai,j aj,k aj,lai,k ak,k ak,l
ai,l ak,l al,l
a
j
akal
W
aTi aTk aTl
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= (1)i+j
|W|1
ai,j aj,k aj,l
ai,k ak,k ak,lai,l ak,l al,l
m1,2 m2,3 m2,4
m1,3 m3,3 m3,4m1,4 m3,4 m4,4
,
j
A{i,j} (1)j1 (j 1)
i
A{i,j} A{i,j} (i 1)
k
l
A{i,j}
k
l
(1)i+j2 = (1)i+j
|A{i,j}||A{k,l}| |A{i,l}||A{j,k}| = (1)i+j+k+l|W|2
ai,j aj,k aj,lai,k ak,k ak,l
ai,l ak,l al,l
m1,2 m2,3 m2,4m1,3 m3,3 m3,4
m1,4 m3,4 m4,4
ai,i ai,j ai,kai,j aj,j aj,k
ai,l aj,l ak,l
m1,1 m1,2 m1,3m1,2 m2,2 m2,3
m1,4 m2,4 m3,4
ai,j aj,j aj,kai,k aj,k ak,k
ai,l aj,l ak,l
m1,2 m2,2 m2,3m1,3 m2,3 m3,3m1,4 m2,4 m3,4
ai,i ai,j ai,lai,k aj,k ak,l
ai,l aj,l al,l
m1,1 m1,2 m1,4m1,3 m2,3 m3,4
m1,4 m2,4 m4,4
.
3 3
|A{i,j}||
A{k,l}| |
A{i,l}||
A{j,k}|
= (1)i+j+k+l|W|2
ai,j aj,k
ai,l ak,l
m1,2 m2,3
m1,4 m3,4
ai,i ai,j ai,k ai,l
ai,j aj,j aj,k aj,l
ai,k aj,k ak,k ak,l
ai,l aj,l ak,l al,l
m1,1 m1,2 m1,3 m1,4
m1,2 m2,2 m2,3 m2,4
m1,3 m2,3 m3,3 m3,4
m1,4 m2,4 m3,4 m4,4
= |A{ik,jl}||A|,
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|A{ik,jl}| = (1)i+j+k+l
aj,i aj,kal,i al,k
ajal
aTi aTk A{ijkl,ijkl}
= (1)i+j+k+l|W|1
ai,j aj,k
ai,l ak,l
ajal
W
aTi aTk
= (
1)i+j+k+l
|W
|1 ai,j aj,kai,l ak,l
m1,2 m2,3
m1,4 m3,4 .
s1(j) s2(j)
s:=p
j=1
{j}
TA(jj)
{j}|ZTZ| T Mconst
|Z{j}TZ{j}|
.
p= 2
s= 22|ZTZ| |Z{1}TZ{1}|2
s=1
2r=1
(1)r+srs|Z{r}TZ{s}| +21|ZTZ|
|Z{2}TZ{2}|2
s=1
2r=1
(1)r+srs|Z{r}TZ{s}|.
2
s=12
r=1(1)r+srs|Z{r}TZ{s}| =21|Z{1}TZ{1}| 212|Z{1}TZ{2}|
+22|Z{2}TZ{2}|
s= 22|ZTZ| |Z{1}TZ{1}||Z{2}TZ{2}|
+21|ZTZ| |Z{1}TZ{1}||Z{2}TZ{2}| + 212|Z{1}TZ{1}||Z{1}TZ{2}|
+ 212|Z{2}TZ{2}||Z{1}TZ{2}| 21|Z{1}TZ{1}|2 22|Z{2}TZ{2}|2.
|ZT
Z| |Z{1}T
Z{1}||Z{2}T
Z{2}| = |Z{1}T
Z{2}|2
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s= 21|Z{1}TZ{1}|2 212|Z{1}TZ{1}||Z{1}TZ{2}| +22|Z{1}TZ{2}|2 21|Z{1}TZ{2}|2 212|Z{2}TZ{2}||Z{1}TZ{2}| +22|Z{2}TZ{2}|2
= 2
j=1
2
r=1
(1)rr|Z{j}TZ{r}|2
.
p= 3
s
s=p
j=1
|ZTZ|
p
s=1s=jp
r=1r=j(1)r+srs|Z{jr}TZ{js}|
|Z{j}TZ{j}|p
s=1
pr=1
(1)r+srs|Z{r}TZ{s}|
=
pj=1
|ZTZ| p
s=1s=j
pr=1r=j
(1)r+srs|Z{jr}TZ{js}| |Z{j}TZ{j}|
2j |Z{j}TZ{j}| + 2pr=1
r=j
(1)r+jrj|Z{j}TZ{r}|
+
ps=1s=j
pr=1r=j
(1)r+srs|Z{r}TZ{s}|
=
pj=1
2j |Z{j}TZ{j}|2 2|Z{j}TZ{j}| p
r=1r=j
(1)r+j rj|Z{j}TZ{r}|
+
ps=1
s=j
pr=1
r=j
(1)r+srs|ZTZ||Z{jr}TZ{js}| |Z{j}TZ{j}||Z{r}TZ{s}|
.
i= j
k= r
l= s
|ZTZ||Z{jr}TZ{js}| |Z{j}TZ{j}||Z{r}TZ{s}| = |Z{j}TZ{r}||Z{j}TZ{s}|
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s=
p
j=1
2j |Z{j}TZ{j}|2 2|Z{j}TZ{j}|p
r=1r=j
(1)r+j
rj |Z{j}T
Z{r}|
ps=1s=j
pr=1r=j
(1)r+srs|Z{j}TZ{r}||Z{j}TZ{s}|
= p
j=1
ps=1
pr=1
(1)r+srs|Z{j}TZ{r}||Z{j}TZ{s}|
= p
j=1 p
r=1(1)rr|Z{j}TZ{r}|
2
,
Z p 2p
j=1
s1(j) =
pj=1
{j}
TA(jj)
{j}|ZTZ| T Mconst
|Z{j}TZ{j}|
+
pr=1
(1)rr|Z{j}TZ{r}|2= 0
pj=1
s2(j) =
pj=1
{j}TA(jj){j}|ZTZ| T Mconst|Z{j}TZ{j}|
pr=1
(1)rr|Z{j}TZ{r}|2
= 2p
j=1
pr=1
(1)rr|Z{j}TZ{r}|2
.
MSE()
MSE()
= 4n2
pj=1
|ZTZ| pr=1(1)rr|Z{j}TZ{r}|2 (n2T M
const + |ZTZ|)3
+43|ZTZ|TT( Mconst)2T
(n2T Mconst
+ |ZTZ|)3.
pj=1
var(j) = 4n2p
j=1
|ZTZ| pr=1(1)rr|Z{j}TZ{r}|2 (n2T M
const + |ZTZ|)3
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BiasT()Bias()
= 4
3|ZTZ|TT( Mconst)2T(n2T M
const + |ZTZ|)3
.
Z Rnp, n > p, p 2
= 0 > 0 [, ]\{0} : MSE()< MSE().
Z
[, ]
[, ]
MSE()
= 4n2
pj=1
|ZTZ| pr=1(1)rr|Z{j}TZ{r}|2 (n2T M
const + |ZTZ|)3
+ O(3)
(n2T Mconst
+ |ZTZ|)3.
|ZTZ| > 0 pj=1 pr=1(1)rr|Z{j}TZ{r}|2 > 0 MSE()
= 0
MSE()
>0, [, 0)0, = 0
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Z
T
Z
Z
T
Z
1= . . .= p= 0
= 0 p
j=1
pr=1
(1)rr|Z{j}TZ{r}|2
>0
= 0
1= 0
2,3= npj=1pr=1(1)rr|Z{j}TZ{r}|2
TT( Mconst
)2T.
Z
limMSE() =
2
pj=1
T{j} A
(jj){j}
T Mconst
+
TT( Mconst
)2T
n2 T Mconst
2 .
1= 0 2= . . .= p= 0
pj=1
s2(j) = 221|ZTZ|p
j=1
|Z{1}TZ{j}|2
TT( Mconst
)2T= n24
1
2
1
p
j=1 |
Z{1}
TZ{j}|2 >0
2=
2
n2121
3=
2
n2121
.
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MSE() =2
23
(22
2
1+ 1)2
+12(
441+221+ 1)
(22
2
1+ 1)2
+14
4(8 + 28221+ 49441)
(2221+ 1)2
= 1
12
142 + 62221+ 6
2441+ 24441+ 84
661+ 147881
(2221+ 1)
2 .
2 =21 = 1
2,3=
1
3= 0.5774.
MSE() = () + Bias()BiasT()
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MtxMSE() =2(ZTZ+2T)1ZTZ(ZTZ+2T)1
+4(ZTZ+2T)1TTT(ZTZ+2T)1
= (ZTZ+2T)1
2ZTZ+4TTT
(ZTZ+2T)1.
:= MtxMSE() MtxMSE() 0
MtxMSE() =2(ZTZ)1
2
ZTZ1 (ZTZ+2T)1 2ZTZ
+4TTT
(ZTZ+2T)1 0.
2 ZTZ+2T Z
TZ1
ZTZ+2T 2ZTZ 4TTT 0
2
ZTZ+ 22T +4T
ZTZ1
T
2ZTZ 4TTT 0
2 22Ip 2TTT +24T ZTZ1 T 0.
0
22 n2
ps=1
pr=1
rsrs
0.
T
T =n
p
r=11r1r . . .p
r=11rpr
pr=1pr1r . . . pr=1prpr
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T
TT= n2
pr=1ps=121rsrs . . .pr=1ps=11prsrs
pr=1
ps=11prsrs . . .
pr=1
ps=1
2prsrs
=n
pr=1
ps=1
rsrsT
.
22T 2TTT=
22 n2p
r=1p
s=1rsrs
T.
c:=
22 n2ps=1pr=1rsrs 0
pTTp 0,
pTcTp= cpTTp 0
p
Rp1
ZTZ
1 = 12 12
ZTZ
ZTZ
1=
VVT1
=V1VT =
1
2 VTT
1
2 VT
pT
cT +24T
ZTZ1
T
p
=cpTTp +24pT
12 VTT
T 1
2 VTT
p 0,
c 0
c 0
c
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j = j
1
Sjj
12
, j= 1, . . . , p
0 = y p
j=1
j Xj .
0
0 = y 1 X1 . . . p Xp
j =
j
1
Sjj
12
, j= 1, . . . , p .
=+ QD1 R(p+1)1,
=
y, 0, . . . , 0T R(p+1)1,
Q=
X1 X2 . . . Xp1 0 . . . 0
0 1 . . . 0
0 0 . . . 1
R
(p+1)p
D=
S11
Spp
Rpp.
Bias() = E(QD1+) = QD1E() + E() .
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E() =
0+1 X1+. . .+pXp
0
0
01
p
=
1 X1+. . .+p Xp
1
p
= Q{0}
T{0} = 1, . . . , p {0} = D1
Bias() =QD1E() QD1
=QD1Bias().
() = (QD1+) =QD
1()D1QT
MSE() = tr
QD1()D1QT
+ BiasT()D
1QTQD1Bias()
= tr
D1QTQD1()
+ BiasT()D1QTQD1Bias().
QTQ=
X21 + 1 X1X2 . . . X1 Xp
X1 X2 X22 + 1 . . .
X2 Xp
X1Xp X2Xp . . . X2
p + 1
=
X21 X1 X2 . . . X1 Xp
X1X2 X22 . . .
X2 Xp
X1Xp X2 Xp . . . X2
p
+ Ip
=
X1
Xp
X1, . . . , Xp + Ip=: XXT + Ip
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D1 XXTD1 =
X21S11
X1
X2S11S22 . . .
X1
XpS11Spp
X1 X2S11
S22
X22S22
. . . X2 Xp
S22
Spp
X1 XpS11
Spp
X2 XpS22
Spp
. . .X2pSpp
,
MSE() = tr
D1( XXT + Ip)D1()
+ Bias()TD1( XXT + Ip)D1Bias()
= tr
D1 XXTD1()
+ tr
D2()
+ Bias()TD1 XXTD1Bias() + Bias()
TD2Bias().
{0}:=
1, . . . ,
p
{0}
pj=1
var(j) = tr
(D1)
= tr
D1()D1= tr D2() .
Q {0}
Bias({0}) =D
1Bias().
MSE({0}) = tr
D2()
+ Bias()
TD2Bias()
=
pj=1
var(j)
Sjj+ Bias()
TD2Bias()
MSE(0) = tr
D1 XXTD1()
+ Bias()TD1 XXTD1Bias()
=
pj=1
pi=1
Xi XjSii
Sjjcov(i ,
j)
+4TT M
constD1 XXTD1 M
const
T
(n2T Mconst
+ |ZTZ|)2.
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X
= 0 >0 [, ]\{0} : MSE()< MSE().
{0}
MSE({0}) =
pj=1
var(
j)Sjj
+
BiasT()D
2Bias()
.
pj=1
var(j)
Sjj= 4n2
pj=1
|ZTZ| pr=1(1)rr|Z{j}TZ{r}|2 Sjj (n2
T Mconst
+ |ZTZ|)3
BiasT()D
2Bias()= 43|ZTZ|TT MconstD2 MconstT
(n2
T
M
const
+ |ZT
Z|)3
.
MSE(
{0})
=0
= 0.
[1, 1]\{0} 1
MSE({0}) = 4n2|ZTZ|
pj=1
pr=1(1)rr|Z{j}TZ{r}|
2Sjj (n2
T Mconst
+ |ZTZ|)3
+ O(3
)(n2T M
const + |ZTZ|)3
.
pr=1
(1)rr|Z{j}TZ{r}|2
>0
(n2T Mconst
+ |ZTZ|)3 >0 Z Sjj
Sjj >0
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var(
0
) = 2p
j=1
p
i=1
(
1)i+j Xi Xj
SiiSjj
n2{i}TA
(ij){j}+ |Z{i}TZ{j}|
n2T Mconst + |ZTZ|
n2p
s=1
pr=1(1)r+srs|Z{i}TZ{r}||Z{j}TZ{s}|n2T M
const + |ZTZ|
2
=2p
j=1
pi=1
(1)i+j XiXjSii
Sjj
2n{i}TA
(ij){j}
n2T M
const + |ZTZ|
n2T Mconst
+ |ZTZ|2
2nT Mconst
n2{i}TA
(ij){j}+ |Z{i}TZ{j}|n2T Mconst + |ZTZ|2
2np
s=1
pr=1(1)r+srs|Z{i}TZ{r}||Z{j}TZ{s}|n2T M
const + |ZTZ|
2
+4n23T M
constp
s=1
pr=1(1)r+srs|Z{i}TZ{r}||Z{j}TZ{s}|
n2T Mconst
+ |ZTZ|3
= 2n2p
j=1p
i=1(1)i+j
XiXjSiiSjj
{i}TA(ij){j}|ZTZ| |Z{i}TZ{j}|T Mconst
n2T Mconst
+ |ZTZ|2
|ZTZ| n2T Mconst
n2T Mconst
+ |ZTZ|3
p
s=1p
r=1(1)r+srs|Z{i}TZ{r}||Z{j}TZ{s}|
.
[2, 2]\{0} 2
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var(0) = 2n2
|ZTZ
|
p
j=1p
i=1(1)i+j
Xi Xj
SiiSjj{i}TA(ij){j}|ZTZ| |ZT{i}Z{j}|T Mconst
n2T Mconst
+ |ZTZ|3
p
s=1
pr=1(1)r+srs|Z{i}TZ{r}||Z{j}TZ{s}|
n2T Mconst
+ |ZTZ|3
+ O(3)
n2T Mconst + |ZTZ|3
Bias(0)
TBias(0) =43|ZTZ|TT MconstD1 XXTD1 MconstT
(n2T Mconst
+ |ZTZ|)3
= O(3)
n2T Mconst
+ |ZTZ|3 .
MSE(0)=0 = 0.
[2, 0)
(0, 2] MSE({0})
MSE() = 0
s+ :=
pj=1
pi=1
(1)i+j Xi Xj
Sii
Sjj
|ZTZ|{i}TA
(ij){j}
|Z{i}TZ{j}|T Mconst
.
p 3
s+ =
pj=1
pi=1
(1)i+j Xi Xj
Sii
Sjj
|ZTZ| p
s=1
s=j
pr=1
r=i
(1)r+srs|Z{ir}TZ{js}|
|Z{i}TZ{j}|p
s=1
pr=1
(1)r+srs|Z{r}TZ{s}|
.
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p
s=1p
r=1(1)r+srs
|Z
{r
}
TZ
{s
}|= (
1)i+jij
|Z
{i
}
TZ
{j
}|+
ps=1s=j
(1)i+sis|Z{i}TZ{s}|
+
pr=1r=i
(1)r+jrj|Z{r}TZ{j}| +ps=1s=j
pr=1r=i
(1)r+srs|Z{r}TZ{s}|
s+
=
pj=1
pi=1
(1)i+j
XiXjSiiSjj (1)i+jij|Z{i}TZ{j}|2
|Z{i}TZ{j}|ps=1s=j
(1)i+sis|Z{i}TZ{s}|
|Z{i}TZ{j}|pr=1r=i
(1)r+jrj|Z{r}TZ{j}|
+
p
s=1s=j
p
r=1r=i
(
1)r+srs |Z
TZ
||Z{
ir
}
TZ{js
}| |Z{
i
}
TZ{j
}||Z{
r
}
TZ{
s
}| .
s+ =
pj=1
pi=1
(1)i+j XiXj
Sii
Sjj
(1)i+jij|Z{i}TZ{j}|2
|Z{i}TZ{j}|p
s=1s=j(1)i+sis|Z{i}TZ{s}|
|Z{i}TZ{j}|pr=1r=i
(1)r+jrj|Z{r}TZ{j}|
ps=1s=j
pr=1r=i
(1)r+srs|Z{i}TZ{s}||Z{j}TZ{r}|
= p
j=1
pi=1
(1)i+j XiXj
Sii
Sjj
ps=1
pr=1
(1)r+srs|Z{i}TZ{s}||Z{j}TZ{r}|
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=
p
i=1p
s=1(1)i+s
Xi
Siis
|Z
{i
}
TZ
{s
}|
p
j=1p
r=1(1)j+r
XjSjj r|Z{j}TZ
{r
}|
=
ps=1
pi=1
(1)i+sXi
Siis|Z{i}TZ{s}|
2.
p= 2
s+ =2
j=1
2i=1
(1)i+j Xi Xj
Sii
Sjj
|ZTZ| 2
s=1s=j
2r=1r=i
rs
|Z{i}TZ{j}|2
s=1
2r=1
(1)r+srs|Z{r}TZ{s}| .
p= 2
2s=1
s=j
2r=1
r=i
rs|ZTZ| (1)r+s|Z{i}TZ{j}||Z{r}TZ{s}|
=2
s=1s=j
2r=1r=i
rs
(1)i+j+r+s|ZTZ| (1)r+s|Z{i}TZ{j}||Z{r}TZ{s}|
= 2
s=1s=j
2r=1r=i
(1)r+srs|Z{i}TZ{s}||Z{j}TZ{r}|.
s+
p = 2
pj=1
pi=1
ps=1
pr=1
(1)i+j+r+s XiXjSii
Sjjrs|Z{i}TZ{r}||Z{j}TZ{s}|
=
p
j=1p
i=1p
s=1p
r=1(1)i+j+r+s
Xi Xj
SiiSjj rs|Z{i}TZ
{s
}||Z{j
}TZ
{r
}|
=
pi=1
ps=1
(1)s+iXi
Siis|Z{i}TZ{s}|
pj=1
pr=1
(1)r+j Xj
Sjjr|Z{j}TZ{r}|
=
pi=1
ps=1
(1)i+sXi
Siis|Z{i}TZ{s}|
2
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var(
0) = 4n2
|ZT
Z|ps=1
pi=1(1)i+s
XiSii
s|Z{i}TZ{s}|2
n2T M
const + |ZTZ|3
+ O(3)
n2T Mconst
+ |ZTZ|3
Z
MSE(0) = 4n2|ZTZ|
ps=1
pi=1(1)i+s
XiSii
s|Z{i}TZ{s}|2
n2T M
const + |ZTZ|
3
+ O(3)n2T M
const + |ZTZ|
3 .
t:=
ps=1
pi=1
(1)i+sXi
Siis|Z{i}TZ{s}|
2 0
t= 0
t > 0
2
MSE(
0)
[2, 0) (0, 2]
:=
min(1, 2) , t >01 , t= 0
Z
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X
X=
1 x1,1 . . . x1,p
1 xn,1 . . . xn,p
Rn(p+1).
=
(X+)T (X+)1
(X+)T y.
= 2
M
quad
x +
M
lin
x +
M
const
x2TAx + 2b
Tx + |XTX| (X+
)T y
=2( M
quadx X
Ty + Mlinx
Ty) +( Mlinx X
Ty + Mconstx
Ty) + Mconstx X
Ty
2TAx + 2bTx + |XTX|
.
X
|X[j]TX[j]| = |XTX[j]| = 0, j = 2, . . . , p
|X[1]TX[1]| = |XTX[1]| = |XTX|.
bTx =|XTX| 0 . . . 0
R1p,
Ax=
|XTX| 0 . . . 00 0 . . . 0
0 0 . . . 0
Rpp.
|Mx| =2|XTX|21+ 2|XTX|1+ |XTX|= |XTX|(221+ 21+ 1).
|X{u}TX{v}[r]| = 0, v=r = 1
|X{u}[r]TX{v}[s]
|= 0, v
=s
= 1
u
=r
= 1.
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b(uv)x T{v} = |X{u}TX{v}[1]| 0 . . . 0 {v}=1|X{u}TX{v}[1]|, v= 1,
b(u1)x
T{1} =|X{u}TX{1}[2]| . . . |X{u}TX{1}[p]|
{1}
=
pr=2
r|X{u}TX{1}[r]|,
T{1} A(11)x {1}= {1}
T|X{1}[2]
TX{1}[2]
| . . .
|X{1}[2]
TX{1}[p]
|
|X{1}[p]TX{1}[2]| . . . |X{1}[p]TX{1}[p]|
{1}
=
pr=2
2r |X{1}[r]TX{1}[r]| + 2p
s=3
s1r=2
rs|X{1}[r]TX{1}[s]|,
{u}TA
(uv)x {v}= {u}
T
|X{u}[1]TX{v}[1]| 0 . . . 00 0 . . . 0
0 0 . . . 0
{v}
=21|X{u}[1]TX{v}[1]|, u, v= 1,
{1}TA
(1v)x {v}= {1}
T
|X{1}[2]TX{v}[1]| 0 . . . 0|X{1}[3]TX{v}[1]| 0 . . . 0
|X{1}[p]TX{v}[1]| 0 . . . 0
{v}
=1
pr=2
r|X{1}[r]TX{v}[1]|, v= 1,
{u}TA
(u1)x {1}= {u}
T
|X{
u
}[1]
TX{1
}[2]
| . . .
|X{
u
}[1]
TX{1
}[p]
|0 . . . 0
0 . . . 0
{1}
=1
pr=2
r|X{u}[1]TX{1}[r]|, u = 1.
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X
u = 1M
quadx X
T + Mlinx
T1up1vn
=21
M
constx X
T1up1vn
,
Mlinx X
T + Mconstx
T1up1vn
= 21
M
constx X
T1up1vn
.
(u, v)
Mquad
x XT
Rpn
u = 1
Mquadx X
T(u, v) =
pr=1
(1)u+rxv,r{u}TA(ur)x {r}
= (1)u+1xv,1{u}TA(u1)x {1}+
pr=2
(1)u+rxv,r{u}TA(ur)x {r}
= (1)u+11xv,1p
r=2
r|X{u}[1]TX{1}[r]|
+21p
r=2
(1)u+rxv,r|X{u}[1]TX{r}[1]|.
Mquadx X
T(u, v) = (1)u+11p
r=2
r|X{u}TX{1}[r]|
+21
pr=2
(1)u+rxv,r|X{u}TX{r}|
=1
pr=2
(1)u+r+1r|X{u}TX{r}| +21p
r=2