In this paper, we review the recent econometric methods related to unit root tests. The central idea is the interaction between structural breaks and unit roots. We consider the standard Dickey-Fuller test and its modifications that allow under the alternative hypothesis one or multiple...

The study examines the methods of testing the presence of unit root and co-integration of time series data using those tests that assumes the presence of breaks and those that assumes no breaks. We employed Eliott et-al(1996) DF-GLS for the latter test and Perron(1997) for the former category....

Recent approaches in unit root testing that take into account the influences of the initial condition, trend, and breaks in the data using pre-testing and performing the union of rejection testing strategies based on the information obtained. This allows for the use of more powerful tests, if...