RDP 9601: Why Does the Australian Dollar Move so Closely with the Terms of Trade? Equation (C4)

a ^ =1.06, b ^ =0.00061, c ^ 1 =0.90, c ^ 2 =0.14, c ^ 3 =0.06, c ^ 4 =0.12, c ^ 5 =0.33, σ ^ ε 1 =0.02 MathType@MTEF@5@5@+=feaagCart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=xfr=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@6F56@