This paper provides a guide to two FORTRAN programs, called TRT1.FOR and TRT2.FOR, written to run the two stages of the Ramsey and Rothman (1996) time reversibility (TR) test. Original FORTAN source code and executable (on an IBM-compatible pc) versions of the programs are available. The major...

Asymmetric behavior has been documented in post-war quarterly U.S. unemployment rates. This suggests that improvement over conventional linear forecasts may be possible through use of nonlinear time series models. In this paper an out-of-sample forecasting competition is carried out for a set of...

Using 15 years worth of additional data, a study is carried out to explore the extent to which the results in Rothman (1991) still hold. Using raw unfiltered data, the aggregate unemployment rate appears to be a Neftci-type symmetric process. But use of two detrending procedures produces strong...