SURGAT: Seasonal Unit Roots Graphical Analysis and Testing device
Ignacio Díaz-Emparanza · RePEc: Research Papers in Economics · 2004
SURGAT is a RATS menu-driven program to help in the analysis of the seasonal component and the trend of a (quarterly, monthly or annual) time series. Once the series is selected, a set of simple transformations may be applied: log, regular difference, seasonal difference, regular+seasonal difference, the series without its deterministic trend, without its deterministic seasonal, estimated efficiently in both cases by means of a deterministic+autoregressive model. The procedure offers several graphs of the series and its transformations: 1- the series, ACF , PACF and spectrum 2- seasonal filters 3- seasonal paths (Buys-Ballot plots) 4- regular paths The program also contains a menu for testing unit roots over the series and its transformations, applying the tests: 1- ADF, 2- HEGY, 3- KPSS, 4- Canova-Hansen.