Mean squared error

Gives the average of the squared differences between estimated values and actual observed values. It is used to measure how accurate a prediction, estimator, or regression model is, with smaller values meaning better fit.

\operatorname{MSE}=\frac{1}{n}\sum_{i=1}^{n}(\hat{Y}_i-Y_i)^2

What the symbols mean

number of observations or data points
index running from 1 to n over the data points
estimated or predicted value for the i-th observation
actual measured value of the i-th observation
mean squared error

About this formula

  • FieldStatistics
  • TopicEstimation and model evaluation
  • LevelUniversity
  • Also calledMSE formula, mean squared error formula, average squared error, mean squared deviation, MSE estimator error, forecast error squared average
  • SourceWikidata Q1940696

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