What is the mean absolute deviation and mean squared error of the following forecast
Day Sales Sale Forecast
24 37
31 41
27 46
29 47
25 50
a) 13, 157
b) 14, 321
c) 16, 312
d) 17, 316
e) 18, 321
Answer: d) 17, 316
Using the first Days of Sales and Sale Forecast as an example,
24 - 37 = -13; 13; 13x13 = 169
Do this for each set of data then add all five errors.
Day Sales Sale Fore Error Error error2
24 37 -13 13 169
31 41 -10 10 100
27 46 -19 19 361
29 47 -18 18 324
25 50 -25 25 625
136 221 -85 85 1579
17 315.8