From 2001 through 2007, average monthly cable TV bills were as shown here.
Year Average Bill
2001...... $32.87
2002........ 34.71
2003........ 36.59
2004........ 38.14
2005........ 39.63
2006........ 41.17
2007........ 42.72
a. Fit a linear trend equation to the time series. Using this equation, determine the trend estimate for 2015.
b. Fit a quadratic equation to the time series, then use the equation to determine the trend estimate for 2015.
c. Which of the preceding equations is the better fi t to the time series if the MAD criterion is used? If the MSE criterion is used?