We study the filter in Ma and Tang (2012) and show that the filter has predictive power for sunspot cycles. The filter is a 12-month simple moving average of the sum of one month, three month and six month differences of the logarithm monthly sunspot number series. We show that this filter leads...

In this paper we study the zero frequency spectral properties of fractionally cointegrated long memory processes and introduce a new frequency domain principal components estimator of the cointegration space and the factor loading matrix for the long memory factors. We find that for fractionally...