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

question 4

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

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