Data from the previous 5 months of a forecasting method is shown below. What is the mean absolute deviation? $$\begin{array} { | c | c | c | c | }
\hline \text { Actual } & \text { Forecast } & \text { Error } & \mid \text { Error } \mid \
\hline 12 & 13 & - 1 & 1 \
\hline 10 & 12 & - 2 & 2 \
\hline 12 & 10 & 2 & 2 \
\hline 8 & 8 & 0 & 0 \
\hline 11 & 10 & 1 & 1 \
\hline
\end{array}$$
A) −1.2
B) 0.0
C) 6.0
D) 1.2

Question

Data from the previous 5 months of a forecasting method is shown below. What is the mean absolute deviation? $$\begin{array} { | c | c | c | c | } 
\hline \text { Actual } & \text { Forecast } & \text { Error } & \mid \text { Error } \mid \
\hline 12 & 13 & - 1 & 1 \
\hline 10 & 12 & - 2 & 2 \
\hline 12 & 10 & 2 & 2 \
\hline 8 & 8 & 0 & 0 \
\hline 11 & 10 & 1 & 1 \
\hline
\end{array}$$
A) −1.2
B) 0.0
C) 6.0
D) 1.2

Quizplus · Accepted Answer

The mean absolute deviation (MAD) is the average of the absolute values of the errors.

MAD = (1+2+2+0+1)/5 = 1.2

Therefore, the answer is D) 1.2.

Data from the Previous 5 Months of a Forecasting Method