Consider the following time series data.
\[\begin{array}{l|rrrrrrr}\text { Month } & 1 & 2 & 3 & 4 & 5 & 6 & 7 \\
\hline \text { Value } & 24 & 13 & 20 & 12 & 19 & 23 & 15\end{array}\]
Construct a time series plot. What type of pattern exists in the data?
a. Develop the three-week moving average forecasts for this time series. Compute MSE and a forecast for week 8
b. Use $\alpha=.2$ to compute the exponential smoothing forecasts for the time series. Compute MSE and a forecast for week 8
c. Compare the three-week moving average approach with the exponential smoothing approach using $\alpha=.2 .$ Which appears to provide more accurate forecasts based on MSE?
d. Use a smoothing constant of $\alpha=.4$ to compute the exponential smoothing forecasts. Does a smoothing constant of .2 or .4 appear to provide more accurate forecasts based on MSE? Explain.