If the Actual Value of a Time Series at Time $\mathrm{MAD}=\frac{\sum_{t=1}^{n}\left|A_{t}-F_{t}\right|}{n}$

Multiple Choice

If the actual value of a time series at time t and the forecast value for time t is denoted by At and Ft respectively, then the formula for the mean absolute deviation over a range of forecasted values is .

A) $\mathrm{MAD}=\frac{\sum_{t=1}^{n}\left|A_{t}-F_{t}\right|}{n}$

B) $\mathrm{MAD}=\frac{\sum_{t=1}^{n}\left(A_{t}-F_{t} \mid\right) ^{2}}{n}$

C) $\mathrm{MAD}=\frac{\sum_{t=1}^{n} \sqrt{\left|A_{t}-F\right|}}{n}$

D) $\mathrm{MAD}=\frac{\sum_{t=1}^{n}\left|\frac{A_{t}-F_{t}}{2}\right|}{n}$