This research estimated the smooth transition autoregressive model with exogenous variables to evaluate the non-linearity of West Texas Intermediate (WTI) crude oil price from the exchange rate of US dollar and WTI crude oil production. The sample period used in this research was the weekly data...

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...