Unit Root Testing in the Presence of Innovation Variance Breaks: a Simple Solution with Increased Power

A New Unit Root Test against Asymmetric ESTAR Nonlinearity with Smooth Breaks

T his paper proposes a new unit root test against the alternative of symmetric or asymmetric exponential smooth transition autoregressive (AESTAR) nonlinearity that accounts for multiple smooth breaks. We provide small sample properties which indicate the test statistics have good empirical size and power. Also, we compared small sample properties of the test statistics with Christop...

Purchasing Power Parity Hypothesis In OIC Countries: Evidence From Panel Unit Root Tests With Heterogeneous Structural Breaks

Testing for Weak-form Efficiency of Crude Palm Oil Spot and Futures Markets: New Evidence from a GARCH Unit Root Test with Multiple Structural Breaks

There is a sizeable literature that tests for weak-form efficiency in commodity and energy spot and futures prices. While many studies now allow for multiple structural breaks to address the criticism that conventional unit root tests have low power to reject the unit root null in the presence of structural change, the extant literature overlooks the fact that conventional unit root tests are b...

Testing Fiscal Reaction Function in Iran: An Application of Nonlinear Dickey-Fuller (NDF) Test

Abstract T his paper is to convince the usage of the nonlinear unit root tests when dealing with a nonlinear model. To do so, the stationary test for variables in a model titles “Fiscal Reaction Function in Iran” has been applied according to both the ordinary and the Nonlinear Dickey-Fuller (NDF) tests. Results show that while variables under investigation are stationary ...

Unit root testing under a local break in trend

Recent approaches to testing for a unit root when uncertainty exists over the presence and timing of a trend break employ break detection methods, so that a with-break unit root test is used only if a break is detected by some auxiliary statistic. While these methods achieve near asymptotic e ciency in both xed trend break and no trend break environments, in nite samples pronounced \valleys" in...