U.S. unemployment rate, part 2.

Using the data from Exercise 50, develop and compare the following models.

a) Fit an appropriate autoregressive model by testing for the significance of each autoregressive term (assume 0.05).

b) Obtain a forecast for March 2007.

c) Compare your forecast for March to the actual value (by computing APE) and to the forecasts obtained in Exercise 50.

d) Recommend an appropriate model for forecasting this time series.