def _transparams(self, params): """ Transforms params to induce stationarity/invertability. Reference --------- Jones(1980) """ p = self.k_ar k = self.k_trend newparams = params.copy() newparams[k:k+p] = _ar_transparams(params[k:k+p].copy()) return newparams
def _transparams(self, params): """ Transforms params to induce stationarity/invertability. Reference --------- Jones(1980) """ k_ar, k_ma = self.k_ar, self.k_ma k = self.k_exog + self.k_trend newparams = np.zeros_like(params) # just copy exogenous parameters if k != 0: newparams[:k] = params[:k] # AR Coeffs if k_ar != 0: newparams[k:k+k_ar] = _ar_transparams(params[k:k+k_ar].copy()) # MA Coeffs if k_ma != 0: newparams[k+k_ar:] = _ma_transparams(params[k+k_ar:].copy()) return newparams
def _transparams(self, params): """ Transforms params to induce stationarity/invertability. Reference --------- Jones(1980) """ k_ar, k_ma = self.k_ar, self.k_ma k = self.k_exog + self.k_trend newparams = np.zeros_like(params) # just copy exogenous parameters if k != 0: newparams[:k] = params[:k] # AR Coeffs if k_ar != 0: newparams[k:k + k_ar] = _ar_transparams(params[k:k + k_ar].copy()) # MA Coeffs if k_ma != 0: newparams[k + k_ar:] = _ma_transparams(params[k + k_ar:].copy()) return newparams