The TSLS estimator is
A) (X'X)-1 X'Y
B) (X'Z(Z'Z)-1 Z'X)-1 X'Z(Z'Z)-1 Z' Y
C) (X-1X)-1(X-1Y)
D) (X'Pz)-1PzY
Question 2
A vector autoregression
A) is the ADL model with an AR process in the error term.
B) is the same as a univariate autoregression.
C) is a set of k time series regressions, in which the regressors are lagged values of all k series.
D) involves errors that are autocorrelated but can be written in vector format.
