This paper extends the cross sectionally augmented panel unit root test proposed by Pesaran (2007) to the case of a multifactor error structure. The basic idea is to exploit information regarding the unobserved factors that are shared by other time series in addition to the variable under consideration. Importantly, our test procedure only requires specification of the maximum number of factors...

In econometric literatures, a number of tests for unit roots have been proposed in the presence of structural changes in I(1) and I(0) model when the numbers of break points are or are not known (though their locations are unknown). Recently [2] proposed a unit root test consisted of two steps: estimating break points and testing a unit root, but their methods resulted in remarkable negative bi...

The prime objective of the study is to identify the long-run and short-run relationship between Indian stock price viz., BSE SENSEX (hereafter named as BSE) and gold price (GOLD) in India. The daily closing price data were collected for the period of ten years ranging from 1st April 2004 to 31st March 2014 with 2490 observations. The study employed two models: Model one us...

The restricted likelihood (RL) of an autoregressive (AR) process of order one with intercept/trend possesses enormous advantages, such as yielding estimates with significantly reduced bias, powerful unit root tests, small curvature and a well-behaved likelihood ratio test (RLRT ) near the unit root. We consider the likelihood ratio test based on the Restricted Likelihood (RLRT ) for the sum of ...

UNIT ROOT TESTING has been developed through numerous papers since the work of Ž . Dickey and Fuller 1979 . The idea is to test the hypothesis that the differences of an observed time series do not depend on its levels, or in other words, the levels of the time series have a unit root that can be removed by differencing. While it is in general possible to have multiple unit roots, only the hypo...

The contribution of this paper is three-fold. Firstly, a characterisation theorem of the sub-hypotheses comprising the seasonal unit root hypothesis is presented which provides a precise formulation of the alternative hypotheses against which regression-based seasonal unit root tests test. Secondly, it proposes regressionbased tests for the seasonal unit root hypothesis which allow a general se...

In this paper we focus on two major issues that surround testing for a unit root in practice, namely: (i) uncertainty as to whether or not a linear deterministic trend is present in the data, and (ii) uncertainty as to whether the initial condition of the process is (asymptotically) negligible or not. In each case simple testing procedures are proposed with the aim of maintaining good power pro...

This article proposes a simple estimator that is consistent for the fraction of a panel that has an autoregressive unit root. Given such an estimate, θ̂ , we can test the null hypothesis that θ = θ0 for any value of θ0 ∈ (0,1]. The test is asymptotically standard normal and is valid whether or not the panel is crosssectionally correlated. The main insight is that in a panel in which some units a...

This paper develops a wavelet (spectral) approach to test the presence of a unit root in a stochastic process. The wavelet approach is appealing, since it is based directly on the different behavior of the spectra of a unit root process and that of a short memory stationary process. By decomposing the variance (energy) of the underlying process into the variance of its low frequency components ...

This paper re-assesses the panel (unit root test) evidence for PPP on four monthly data sets. We discuss and illustrate that commonly-used first generation panel unit root tests are inappropriate for PPP analysis since they are constructed for cross-sectionally uncorrelated panels. Given that real exchange rate panel data sets are – almost by construction – highly cross-sectionally correlated, ...