1. A computer-implemented method for determining a parametric model to process time series data with respect to regressor components and autoregressive components, comprising: receiving time series data; performing a first stepwise statistical technique upon autoregressive components using the time series data and determining significance level of an autoregressive component while performing the first stepwise statistical technique; performing a second stepwise statistical technique upon regressor components using the time series data and determining significance level of a regressor component while performing the second stepwise statistical technique; including, in a parametric model, autoregressive and regressor components based upon the autoregressive and regressor components' significance levels; wherein the parametric model is a predictive model of the time series data and adjusts for autocorrelation in the time series data.