Refer to the data given in Problem 16.16 on page 682 (and stored in SolarPower) that represent the yearly amount of solar power installed (in megawatts) in the United States from 2000 through 2008.
a. Fit a third-order autoregressive model to the amount of solar power installed and test for the significance of the third-order autoregressive parameter. (Use α = 0.05.)
b. If necessary, fit a second-order autoregressive model to the amount of solar power installed and test for the significance of the second-order autoregressive parameter. (Use α = 0.05.)
c. If necessary, fit a first-order autoregressive model to the amount of solar power installed and test for the significance of the first-order autoregressive parameter. (Use α = 0.05.)
d. Forecast the yearly amount of solar power installed (in megawatts) in the United States in 2009 and 2010.