How to Calculate Mean Absolute Error
- 1). Set up the data by making two columns of data. One column should have the predicted values, or estimated values. The other should have the actual values.
- 2). Subtract the predicted value from the actual value in each row.
- 3). Take the absolute value of each row. That is, if the difference is negative, remove the negative sign. If it is positive, leave it as is.
- 4). Add up the absolute values.
- 5). Divide by n, that is, the total number of rows.
