The basic structural time series model has been designed for the modelling and forecasting of seasonal economic time series. In this paper we explore a generalisation of the basic structural time series model in which the time-varying trigonometric terms associated with different seasonal...

Structural change affects the estimation of economic signals, like the underlying growth rate or the seasonally adjusted series. An important issue, which has at- tracted a great deal of attention also in the seasonal adjustment literature, is its detection by an expert procedure. The...

In the present paper we study the effects in econometric inference when ussing seasonal adjusted data obtained by signal extraction filters. In particular we analyze the effects in the integration order in zero frequency of the adjusted series. We center our study in the consequences of the...