ROBUST UNIT ROOT TESTS FOR SEASONAL AUTOREGRESSIVE PROCESS

  • Oh, Yu-Jin (Department of Statistics, Ewha Womans University) ;
  • So, Beong-Soo (Department of Statistics, Ewha Womans University)
  • 발행 : 2003.05.23

초록

The stationarity is one of the most important properties of a time series. We propose robust sign tests for seasonal autoregressive process to determine whether or not a time series is stationary. The tests have an exact binomial null distribution and are robust to the outliers and the heteroscedastic errors. Monte-Carlo simulation shows that the sign test is locally more powerful than the OLSE-based tests for heavy-tailed and/or heteroscedastic error distributions.

키워드