This Paper Proposes Some New Tests for Detecting the Presence of a Unit Root in Quite General Time Series Modesl. Our Approach Is Nonparametric with Respect to Nuisance Parameters and Thereby Allows for a Very Wide Class of Weakly Dependent and Possibly Heterogeneously Distributed Data. the...

We Consider the Null Hypothesis That a Time Series Has a Unit Root with Possibly Non-Zero Drift Against the Alternative That the Process Is 'Trend-Stationary'. the Interest Is That We Allow Under Both the Null and Alternative Hypotheses for the Presence of a One-Time Change in the Level Or in...

This Paper Studies Tests of Joint Hypotheses in Time Series Regression with a Unit Root in Which Weakly Dependent and Heterogeneously Distributed Innovations Are Allowed. We Consider Two Types of Regression: One with a Constant and Lagged Dependent Variable, and the Other with a Trend Added. the...