7. Assessing the smoothers for MA(2) with n = 500, b1 = −0.8, b2 = 0.7:

(i) Simulate the data.

(ii) Fit the periodogram to the data and plot it with “log(spec)” as the y variable and “freq” as the x variable.

(iii) Add a line with the smoothed data (each type of smoother).

When done, there will be three plots: each will have the same periodogram and true model and a different smoother.

(iv) Which smoother is best? Which is worst? Explain.

(v) Turn in your R code with each plot.