Question

You have sales from January to April of 132,126,58, and 108 . Your forecasts for those months were 138,112,53, and 99 respectively. What is your mean absolute percentage error for those four months? Answer to one decimal place.

Answer 1

The mean absolute percentage error is 8.2% for the four months.

Step-by-step explanation:

The mean absolute percentage error (MAPE) is a measure of the accuracy of a forecasting model.

To calculate the MAPE for the given sales and forecasts, we first find the absolute difference between the actual sales and the forecasted sales for each month, then divide it by the actual sales and multiply by 100 to get the percentage. Finally, we calculate the mean of these percentages.

Using the formula:

MAPE = (|Actual - Forecast| / Actual) * 100

For the given sales and forecasts:

January: MAPE = (|132-138| / 132) * 100 = 4.55%

February: MAPE = (|126-112| / 126) * 100 = 11.11%

March: MAPE = (|58-53| / 58) * 100 = 8.62%

April: MAPE = (|108-99| / 108) * 100 = 8.33%

To find the mean MAPE, we calculate the average of these percentages:

Mean MAPE = (4.55 + 11.11 + 8.62 + 8.33) / 4 = 8.15%

Therefore, the mean absolute percentage error for the four months is 8.2% (rounded to one decimal place).