AI engineering glossary · Evaluation metrics

What is MAPE (mean absolute percentage error)?

Mean absolute percentage error (also called MAPE): The average of the absolute errors expressed as a percentage of the true values: (100/N) * sum of |y - y_hat| / |y|. It is easy to communicate but breaks down when true values are zero or near zero, and it penalises over-forecasts more than under-forecasts.

Level: beginnerTopic: Evaluation metrics

Mean absolute percentage error: an example

For actuals 50, 60, 70, 80 and predictions 55, 58, 72, 100 the percentage errors are 10%, 3.3%, 2.9% and 25%, giving MAPE of about 10.3%.

Related terms

More Evaluation metrics terms

Where you learn it

Mean absolute percentage error is part of the AI Engineering Program, which teaches it with notes, a hands-on lab and an exam. The first lesson is free.

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