Ph. Franses et F. Kleibergen, UNIT ROOTS IN THE NELSON-PLOSSER DATA - DO THEY MATTER FOR FORECASTING, International journal of forecasting, 12(2), 1996, pp. 283-288
In this paper we compare two univariate time series models, i.e. one w
ith and one without an imposed unit root, in a forecasting experiment
for the fourteen annually observed US data analyzed by Nelson and Plos
ser (1982, Journal of Monetary Economics 10, 138-162). Our main result
is that the unit root mode! is regularly preferred. This result holds
for a variety of sample sizes and forecast horizons as well as for on
e-step and multi-step ahead forecasts.