AI engineering glossary · Evaluation metrics

What is MSLE (mean squared logarithmic error)?

Mean squared logarithmic error (also called MSLE): The mean of squared differences between the natural logs of (1 + prediction) and (1 + actual). It measures relative rather than absolute error, so it treats being off by a factor as equally bad at small and large scales. It suits targets spanning orders of magnitude, but needs non-negative values.

Level: advancedTopic: Evaluation metrics

Mean squared logarithmic error: an example

Predicting 200 for an actual 100 gives a squared log error of about 0.47; predicting 1,100 for an actual 1,000 gives only about 0.009.

Related terms

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Where you learn it

Mean squared logarithmic 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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