A unit root test based on smooth transitions and nonlinear adjustment

Hepsag, Aycan (2017): A unit root test based on smooth transitions and nonlinear adjustment.

Abstract

In this paper, we develop a new unit root testing procedure which considers jointly for structural breaks and nonlinear adjustment. The structural breaks are modelled by means of a logistic smooth transition function and nonlinear adjustment is modelled by means of an ESTAR model. The empirical size of test is quite close to the nominal one and in terms of power; the new unit root test is generally superior to the alternative test. The new unit root test presents good size properties and does not lead to over-rejections of the null hypothesis of the unit root.

• Item Type: MPRA Paper
• Language: English
• Keywords: Smooth transitions, nonlinearity, unit root, ESTAR
• Subjects: C - Mathematical and Quantitative Methods > C1 - Econometric and Statistical Methods and Methodology: General > C12 - Hypothesis Testing: General; C - Mathematical and Quantitative Methods > C2 - Single Equation Models ; Single Variables > C22 - Time-Series Models ; Dynamic Quantile Regressions ; Dynamic Treatment Effect Models ; Diffusion Processes

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