We test for mean reversion in real exchange rates using data from five countries, four of which have experienced episodes of high inflation. Using monthly data for Argentina, Brazil, Chile, Colombia, and Israel, we find that a stochastic unit root model is typically appropriate (Brazil is the...

The two most commonly applied tests of the null hypothesis of a unit autoregres-sive root in a time series generating process are examined. Simple theoretical calculations, confirmed by simulation evidence, suggest that the probabilities of rejection of the null hy-pothesis of those tests can...

In the context of regression-based (quarterly) seasonal unit root tests, we examine the impact of initial conditions (one for each quarter) of the process on test power. We investigate the behaviour of the well-known OLS detrended HEGY seasonal unit root tests together with their...

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...

type="main" xml:id="obes12037-abs-0001" <title type="main">Abstract</title> <p>In this article, we consider estimating the timing of a break in level and/or trend when the order of integration and autocorrelation properties of the data are unknown. For stationary innovations, break point estimation is commonly performed by...</p>

In this paper we develop a testing procedure for the presence of a deterministic linear trend in a univariate time series which is robust to whether the series is I(0) or I(1) and requires no knowledge of the form of weak dependence present in the data. Our approach is motivated by the testing...

We propose methods for constructing confidence sets for the timing of a break in level and/or trend that have asymptotically correct coverage for both I(0) and I(1) processes. These are based on inverting a sequence of tests for the break location, evaluated across all possible break dates. We...