Final answer:
To calculate the Mean Absolute Deviation (MAD) for the given dataset, the absolute deviations of each pair of actual and forecast values are calculated, followed by the average of these deviations. The MAD for the actual values (20, 30) and forecast values (25, 25) is 5. The correct option is b. 5
Step-by-step explanation:
The Mean Absolute Deviation (MAD) is a measure of the average absolute deviations of data values from their mean. To calculate MAD for the given values, we subtract each forecast value from the actual value, take the absolute value of each, and then find the average of those absolute values. For the actual values of 20 and 30, and forecast values of 25 and 25, the calculations would be as follows:
Absolute deviation for the first pair: |20 - 25| = 5
Absolute deviation for the second pair: |30 - 25| = 5
MAD = (5 + 5) / 2 = 5
The MAD for the given data set is 5.