Unit Roots in Time Series with Changepoints

Testing for unit roots in time series with level shifts

Tests for unit roots in univariate time series with level shifts are proposed and investigated The level shift is assumed to occur at a known time It may be a simple one time shift which can be captured by a dummy variable or it may have a more general form which can be modeled by some general nonlinear transition function There may also be more than one shift point and there may be other deter...

Testing for seasonal unit roots in monthly panels of time series

We consider the problem of testing for seasonal unit roots in monthly panel data. To this aim, we generalize the quarterly CHEGY test to the monthly case. This parametric test is contrasted with a new nonparametric test, which is the panel counterpart to the univariate RURS test that relies on counting extrema in time series. All methods are applied to an empirical data set on tourism in Austri...

Inference on Unit Roots and Trend Breaks in Macroeconomic Time Series

a time-series analysis of the demand for life insurance in iran

با توجه به تجزیه و تحلیل داده ها ما دریافتیم که سطح درامد و تعداد نمایندگیها باتقاضای بیمه عمر رابطه مستقیم دارند و نرخ بهره و بار تکفل با تقاضای بیمه عمر رابطه عکس دارند

Filtering Permanent Cycles with Complex Unit Roots

Separating cyclical movement from trend growth at seasonal and business cycle frequencies is important to macroeconomic research. At business cycle frequencies, time trends, first differences and the more recent Hodrick-Prescott (HP) filter are used to separate trends from cycles. At seasonal frequencies, ad-hoc methods like the Census Bureau’s X-11 seasonal filter are applied. This paper revie...