This paper documents the function and use of the Gretl function package VCwrapper.pdf that implements the VC method for estimating time-varying coefficients in linear models as described in Schlicht (2021). It builds on the VCC program by Schlicht (2021a), is easy to use and highly configurable....

The estimation of models with time-varying coefficients is usually performed by Kalman-Bucy filtering. The two-sided filter proposed by Schlicht (1988) is statistically and computationally superior to the one-sided Kalman-Bucy filter. This paper describes the estimation procedure and the program...

This note gives a fairly complete statistical description of the Hodrick-Prescott Filter (1997), originally proposed by Leser (1961). It builds on an approach to seasonal adjustment suggested by Leser (1963) and Schlicht (1981, 1984). A moments estimator for the smoothing parameter is proposed...