Deterministic or Stochastic Trend Decision on the Basis of the Augmented Dickey-Fuller Test

Time series with deterministic and stochastic trends possess different memory characteristics and exhibit dissimilar long-range development. Trending series are nonstationary and must be transformed to be stabilized. The choice of correct transformation depends on patterns of nonstationarity in the data. Inappropriate transformations are consequential for subsequent analysis and should be omitted. The objectives of this article are ( 1) to introduce unit root testing procedures, ( 2) to evaluate the strategies for distinguishing between stochastic and deterministic alternatives by means of Monte Carlo experiments, and ( 3) to demonstrate their implementation on empirical examples using SAS for Windows.