# Question

For the data of Exercise 18.11:

a. Obtain the centered moving average for N = 4; for N = 12.

b. When N = 12 months, the centered moving average is relatively smooth compared to when N = 4. Aside from the fact that it includes a greater number of months at a time, is there any other reason why the moving average with N = 12 should be so smooth?

a. Obtain the centered moving average for N = 4; for N = 12.

b. When N = 12 months, the centered moving average is relatively smooth compared to when N = 4. Aside from the fact that it includes a greater number of months at a time, is there any other reason why the moving average with N = 12 should be so smooth?

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