When the Underlying Mean of a Time Series Is Very

Multiple Choice

When the underlying mean of a time series is very stable and there are no trend, cyclical, or seasonal influences:

A) a simple moving-average forecast with n = 20 should outperform a simple moving-average forecast with n = 3.
B) a simple moving-average forecast with n = 3 should outperform a simple moving-average forecast with n = 15.
C) a simple moving-average forecast with n = 20 should perform about the same as a simple moving-average forecast with n = 3.
D) an exponential smoothing forecast with a = 0.30 should outperform a simple moving-average forecast with α = 0.01.