6. Testing linear restrictions
6.1. Design of the generalized eigenvalue problem, and asymptotic distribution theory
Following Johansen (1988,1991), we now focus on the problem of how to test whether
a cointegrating vector ξ satisfies a linear relation of the form
(29)
H0: ξ = Hφ , where rank(H) s s ≤ r, φ ∈ Bs.
Thus, the matrix H is of full column rank s. At first sight we may think of mimicking
Johansen’s test for these linear restrictions, on the basis of the matrices Am and IBm + n2Âm-1.
However, that leads to a case-dependent asymptotic null distribution. Therefore we propose
the following alternative approach, on the basis of the matrix Aim only.
First, note that the null hypothesis (29) implies
H R RrΓ, (30)
where Γ is a r × s matrix of rank s. Then it follows straightforwardly from (15), (17) and (30)
that
D m
n2HAmH n n2ΓTR,TA,RrΓ →ΓTRrTD(1)£γ2YYtTD(1)TRrΓ
k= 1
and
HTÂ + n 2A ^1 H = ΓtR∕r(r⅛4 +n 2Â1)r) RTR Γ→ ΓTV Γ.
∖ m m∣ r ∖ ∖ m m∣∣ r r, m
Since similarly to (21) we can write
Y" - (γtR∕D(1)D(1)TRrΓ■’ΓTR,TD(1)Yt (~ N,^[0,Is]),
we have that
Theorem 4. If there are r cointegrating vectors then under the null hypothesis (29) the
ordered solutions of the eigenvalues problem
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