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with solution<br />

a= C−1 z c zs′<br />

, γ = m′−c<br />

C<br />

−1<br />

z m z , (A7)<br />

s ˆ′ = m′+c C<br />

− 1 ( z −m<br />

T<br />

z s′<br />

z<br />

z<br />

)<br />

T<br />

z s ′<br />

= aT<br />

C<br />

T<br />

T −<br />

za+<br />

σ<br />

s<br />

2 ′<br />

−2a<br />

c z s ′ = σ 2<br />

s ′<br />

−c<br />

z s ′ C<br />

1<br />

z c zs′<br />

(A8)<br />

φ . (A9)<br />

Since the above prediction is already unbiased from (A6) it<br />

follows that it is identical with the Best Quadratic Unbiased<br />

inhomogeneous prediction (inhomBQUP = inhomBQP).<br />

Best quadratic homogeneous prediction (homBQP):<br />

Unconditional minimization of φ follows from<br />

1 ⎛ ∂φ<br />

⎞<br />

⎜ ⎟<br />

2 ⎝ ∂a<br />

⎠<br />

T<br />

⎛ ∂β<br />

⎞<br />

= β ⎜ ⎟<br />

⎝ ∂a<br />

⎠<br />

T<br />

+ C<br />

a−<br />

z c z s′<br />

=<br />

( mT<br />

a−m<br />

′)<br />

m + C a−c<br />

0 , (A10)<br />

= z z z zs′<br />

=<br />

with solution<br />

a= ( C + m mT<br />

)<br />

1(<br />

c ′<br />

=<br />

z<br />

z<br />

z<br />

+ m′<br />

m<br />

−<br />

zs<br />

z )<br />

m′−c<br />

C<br />

m<br />

T −1<br />

z z z<br />

C<br />

−1<br />

′<br />

z c z<br />

C<br />

−1<br />

′ + s<br />

s<br />

z<br />

1+<br />

mT<br />

z C<br />

−1<br />

z m z<br />

=<br />

m<br />

z<br />

, (A11)<br />

mT<br />

−<br />

⎛<br />

−<br />

z C<br />

1<br />

z z<br />

mT<br />

⎞<br />

′=<br />

′+<br />

−<br />

z C<br />

1<br />

z z<br />

s ˆ<br />

m<br />

T<br />

c<br />

⎜ −<br />

⎟<br />

′<br />

+<br />

−<br />

z<br />

C<br />

1<br />

z z<br />

m<br />

⎝ +<br />

− z<br />

1 m z C<br />

1<br />

z m s<br />

,<br />

T<br />

z<br />

1 mT<br />

z C<br />

1<br />

z m z ⎠<br />

(A12)<br />

c C m −m′<br />

β =<br />

, (A13)<br />

m<br />

T −1<br />

z s ′ z z<br />

1+<br />

1<br />

mT<br />

z C−<br />

z<br />

z<br />

( m′−c<br />

C m z )<br />

2<br />

φ = σ<br />

2<br />

c<br />

z<br />

C<br />

−1<br />

′<br />

−<br />

T<br />

s s ′ z c zs′<br />

+<br />

. (A14)<br />

1+<br />

m C m<br />

T<br />

z s ′<br />

T<br />

z<br />

−1<br />

z<br />

−1<br />

z<br />

Best quadratic unbiased homogeneous prediction<br />

(homBQUP):<br />

Minimization of φ under the condition β = 0 , requires the<br />

formulation of the Lagrangean function L = φ −2λβ<br />

and the<br />

solution is provided from the equations<br />

1 ⎛ ∂L<br />

⎞<br />

⎜ ⎟<br />

2 ⎝ ∂a<br />

⎠<br />

T<br />

⎛<br />

= β ⎜<br />

⎝<br />

T<br />

∂β<br />

⎞<br />

⎟<br />

∂a<br />

⎠<br />

+ C<br />

z<br />

a−c<br />

= z z zs′<br />

=<br />

zs′<br />

z<br />

⎛<br />

−λ<br />

⎜<br />

⎝<br />

T<br />

∂β<br />

⎞<br />

⎟<br />

∂a<br />

⎠<br />

( β −λ)<br />

m + C a−c<br />

0 , (A15)<br />

1 ∂L<br />

=−β<br />

= m′−a T m z = 0 , (A16)<br />

2 ∂λ<br />

Since β = 0 (A15) gives<br />

a= C λ (A17)<br />

−<br />

z<br />

1 c zs′<br />

+ C z<br />

−1 m z<br />

which can be inserted into (A16) to provide<br />

m′−c<br />

λ =<br />

m<br />

C<br />

m<br />

T −1<br />

z s ′ z z<br />

T<br />

z C<br />

−1<br />

z m z<br />

=<br />

(A18)<br />

with the above values of a and λ the prediction and its<br />

mean square error become<br />

mT<br />

−<br />

⎛ −<br />

′ =<br />

z C<br />

1<br />

z z<br />

mT<br />

′+ −<br />

⎜<br />

−<br />

′ −<br />

z C<br />

1<br />

z z<br />

s ˆ<br />

m<br />

T<br />

c<br />

z<br />

C<br />

1<br />

z z<br />

m<br />

mT<br />

−<br />

z C<br />

1<br />

z m s<br />

z<br />

⎝ mT<br />

z C<br />

1<br />

z m z<br />

T −1<br />

z s ′ z z<br />

T 1<br />

z C<br />

−<br />

z m z<br />

z<br />

⎞<br />

⎟<br />

⎠<br />

(A19)<br />

( m′−c<br />

C m )<br />

2<br />

φ = σ<br />

2<br />

c<br />

z<br />

C<br />

−1<br />

′<br />

−<br />

T<br />

s s ′ z c zs′<br />

+<br />

. (A20)<br />

m<br />

6

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