Mean Percentage Error (MPE)

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Mean percentage error (MPE) is the arithmetic mean of errors from modeling.

• closely related to Mean Squared Deviation (MSD)
• compares expected values to actual values and calculates mean error
• error is defined as any deviation from the planned or expected value
• critical in modeling
  • used to evaluate the efficacy of the model itself
• formula:
  • is the number of different times for which the variable is forecast
  • is the actual value of the quantity being forecast
  • is the forecast
• metric is describing the difference between expected values and the actual value
  • effective way to measure the impact of an incident