A Time Series Is Shown in the Table Below A Plot the Time Series to Determine Which of the

Essay

A time series is shown in the table below: $$\begin{array} { | c | c | } \hline \text { Time period } & y _ { t } \\\hline 1 & 48 \\2 & 50 \\3 & 46 \\4 & 42 \\5 & 40 \\6 & 32 \\7 & 34 \\8 & 26 \\9 & 21 \\10 & 13 \\\hline\end{array}$$ a. Plot the time series to determine which of the trend models appears to fit better.
b. Use the regression technique to calculate the linear trend line and the quadratic trend line. Which line fits better? Use the best model to forecast the value of y for time period 7.