BIC.logLik               package:nlme               R Documentation

BIC of a logLik Object

Description:

     This function calculates the Bayesian information criterion, also
     known as Schwarz's Bayesian criterion (SBC) for an object
     inheriting from class 'logLik', according to the formula 
     log-likelihood + npar*log(nobs), where npar represents the number
     of parameters  and nobs the number of  observations in the fitted
     model. When comparing fitted objects, the smaller the BIC, the
     better the fit.

Usage:

     ## S3 method for class 'logLik':
     BIC(object, ...)

Arguments:

  object: an object inheriting from class 'logLik', usually resulting
          from applying a 'logLik' method to a fitted model object.

     ...: some methods for this generic use optional arguments. None
          are used in this method.

Value:

     a numeric value with the corresponding BIC.

Author(s):

     Jose Pinheiro Jose.Pinheiro@pharma.novartis.com and Douglas Bates
     bates@stat.wisc.edu

References:

     Schwarz, G. (1978) "Estimating the Dimension of a Model", Annals
     of Statistics, 6, 461-464.

See Also:

     'BIC', 'logLik', 'AIC'.

Examples:

     fm1 <- lm(distance ~ age, data = Orthodont) 
     BIC(logLik(fm1))

