NBER Publications by Pierre Perron

This paper is an introduction to unit root econometrics as applied in macroeconomics. The paper first discusses univariate time series analysis, emphasizing the following topics: alternative representations of unit root processes, unit root testing procedures, the power of unit root tests, and the interpretation of unit root econometrics in finite samples. A second part of the paper tackles similar issues in a multivariate context where cointegration is now the central concept. The paper reviews representation, testing, and estimation of multivariate time series models with some unit roots. Two important themes of this paper are first, the importance of correctly specifying deterministic components of the series; and second, the usefulness of unit root tests not as methods to uncover some ...

Power functions of tests of the random walk hypothesis versus stationary first order autoregressive alternatives are tabulated for samples of fixed span but various frequencies of observation.