Two new features have been added to the AUTOREG procedure.
An alternative test for stationarity, proposed by Kwiatkowski, Phillips, Schmidt, and Shin (KPSS), is implemented. The null hypothesis for this test is a stationary time series, which is a natural choice for many applications. Bartlett and quadratic spectral kernels for estimating long-run variance can be used. Automatic bandwidth selection is an option.
Corrected Akaike information criterion (AICC) is implemented. This modification of AIC corrects for small-sample bias. Along with the corrected Akaike information criterion, the mean absolute error (MAE) and mean absolute percentage error (MAPE) are now included in the summary statistics.