A Simple Panel Stationarity Test in the Presence of Cross-Sectional Dependence with an Application

• Activity Number: 475
• Type: Contributed
• Date/Time: Wednesday, August 3, 2011 : 8:30 AM to 10:20 AM
• Sponsor: Business and Economic Statistics Section
• Author(s): Kaddour Hadri*+
• Companies: Queen's University at Belfast
• Keywords: Panel data ; stationarity ; KPSS test ; cross-sectional dependence ; joint asymptotic ; Prebish-Singer hypothesis

Abstract

This paper develops a simple test for the null hypothesis of stationarity in heterogeneous panel data with cross-sectional dependence in the form of a common factor in the disturbance. We do not estimate the common factor but mop-up its effect by employing the same method as the one proposed in Pesaran (2007) in the unit root testing context. Our test is basically the same as the KPSS test but the regression is augmented by cross-sectional average of the observations. The limiting distribution under the null is shown to be a standard normal. The latter result is derived using the joint asymptotic limits where T and N?8 simultaneously (under the additional condition that N/T?0). We also extend our test to the more realistic case where the shocks are serially correlated. We use Monte Carlo simulations to examine the finite sample property of the panel augmented KPSS test. An application is also provided where the proposed panel stationary test is applied in the first step when testing the secular decline of real commodity prices known as the Prebish-Singer (PS) hypothesis.