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Mean Absolute Error (MAE)

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TL;DR. The average absolute difference between predictions and true values.

Technical Definition

The average absolute difference between predictions and true values.

How it works

MAE = (1/n) Σ |ŷᵢ − yᵢ|. More robust to outliers than MSE because it doesn't square errors. Often easier to communicate to non-technical stakeholders ('our forecast is off by 3 units on average').

Related Concepts

  • Loss Function — A mathematical function that measures how far the model's predictions are from the actual values, guiding the learning process.
  • Regression — A supervised learning task that predicts a continuous numeric value.
  • Mean Squared Error (MSE) — The average squared difference between predictions and true values.