The following data, stored in NASCAR, provide the number of accidents in the NASCAR Sprint Cup series from 2001 to 2009:
Year Accidents
2001........................200
2002........................186
2003........................235
2004........................204
2005........................253
2006........................237
2007........................240
2008........................211
2009........................195
a. Plot the time series.
b. Fit a three-year moving average to the data and plot the results.
c. Using a smoothing coefficient of W = 0.50, exponentially smooth the series and plot the results.
d. What is your exponentially smoothed forecast for 2010?
e. Repeat (c) and (d), using W = 0.25.
f. Compare the results of (d) and (e).