2. Convert monthly data into quarterly/seasonal time series and estimate the following regression model that uses an exponential trend and quarterly/seasonal dummy variables. The model is: ln (PAt)= alpha0 + alpha1 TIMEt + alpha2 MARt + alpha3 SEPt + alpha4 DECt + ?t (1) Where: PAt = quarterly passenger arrivals. ?t = random error. Estimate the model, calculate the MAPE statistic and discuss the results. Produce fitted values and show these and the actual data in a graph. In light of the MAPE statistics (calculated above), rank the models according to their ability to forecast the future.