Dickey Fuller - ADF test

[andreas.zaras]

Hello,


1) DYt=psi*Yt-1 + ut (none)

2) DYt=intercept+psi*Yt-1 + ut (intercept)

3) DYt=intercept + time trend + psi*Yt-1 + ut (trend and intercept)

In order to conduct DF test it should be tested:
H0: psi=0
H1:psi not 0
in the above three equations. E Views names these equations (none), (trend and intercept) and (intercept) in th Unit Root test window.
If we have a series and we want to test its stationarity status, on what criteria, tests, visual hints or anything else should we select one of the three equations (options)?.

Thnaks in advance,


Andreas