is an option for LinearModelFit and other fitting functions that specifies whether a constant term should be included if not explicitly given in the list of basis functions.


  • The default setting IncludeConstantBasis->True adds a constant basis to the model if one is not specified in the list of basis functions.
  • Linear and generalized linear models typically compare the fitted model to the mean response model, which contains only a constant basis function.
  • Setting IncludeConstantBasis->False can be used to fit models without a constant basis function.


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Basic Examples  (1)

Fit a simple linear regression model:

Fit the linear model with intercept zero:

Scope  (2)

Fit a generalized linear model:

Fit the model without a constant term in the linear predictor:

Fit logit models with and without a constant term:

Probit models:

Introduced in 2008