Akaike information criterion

Scores a statistical model by its maximised likelihood penalised for the number of parameters, so that lower values indicate a better trade-off between fit and complexity. It is used to compare candidate models fitted to the same data.

\mathrm{AIC} = 2k - 2\ln\left(\max_{\theta_1,\dotsc,\theta_k}\Pr(x_1,\dotsc,x_n \mid \theta_1,\dotsc,\theta_k)\right)

What the symbols mean

Akaike information criterion value (lower is better)
number of estimated parameters in the model
number of observations
observed data realisations
model parameters
likelihood function of the parameters given the data

About this formula

  • FieldStatistics
  • TopicModel selection
  • LevelUniversity
  • Also calledAIC, model selection criterion, AIC formula, maximum likelihood model selection, information criterion for model comparison, Akaike criterion
  • SourceWikidata Q1662573

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