This paper generalises the monthly seasonal unit root tests of Franses (1991) for a heterogeneous panel following the work of Im, Pesaran, and Shin (2003), which we refer to as the F-IPS tests. The paper presents the mean and variance necessary to yield a standard normal distribution for the...

This paper extends the cross-sectionally augmented IPS (CIPS) test of Pesaran (2006) to a three-dimensional (3D) panel. This 3D-CIPS test is correctly sized in the presence of cross-sectional dependency. Comparing its power performance to that of a bootstrapped IPS (BIPS) test, we find that the...

This paper applies a pairwise approach to investigate the validity of the law of one price in the crude oil markets. Price differentials appear smaller between crude oil pairs with similar physical/chemical characteristics and also for pairs within OPEC.

We adopt time-series and cross-section methods to analyse long-term relationships between pairs of crude oil prices and assess how physical and institutional factors affect their speed of reaction to exogenous shocks. Using a methodological approach which does not require identifying specific...

The panel variant of the KPSS tests developed by Hadri (2000) for the null of stationarity suffers from size distortions in the presence of cross section dependence. However, applying the bootstrap methodology we find that these tests are approximately correctly sized.

This paper presents two alternative methods for modifying the HEGY-IPS test in the presence of cross-sectional dependency. In general, the bootstrap method (BHEGY-IPS) has greater power than the method suggested by Pesaran (2007) (CHEGY-IPS), although for large T and high degree of...

This paper uses the approach of Im, Pesaran and Shin (2003) to propose seasonal unit root tests for dynamic heterogeneous panels based on the means of the individuals HEGY test statistics. The standardised t-bar and F-bar statistics are simply averages of the HEGY tests across groups. These...

This paper estimates response surface coefficients for a large range of quantiles of the cross-sectionally augmented IPS (CIPS) test of Pesaran (<CitationRef CitationID="CR13">2007</CitationRef>), for different specifications of the deterministic components. An Excel programme is available to calculate the P value associated with a CIPS...</citationref>