deviance.glmnet {glmnet} | R Documentation |
Extract the deviance from a glmnet object
Description
Compute the deviance sequence from the glmnet object
Usage
## S3 method for class 'glmnet'
deviance(object, ...)
Arguments
object |
fitted glmnet object |
... |
additional print arguments |
Details
A glmnet object has components dev.ratio
and nulldev
. The
former is the fraction of (null) deviance explained. The deviance
calculations incorporate weights if present in the model. The deviance is
defined to be 2*(loglike_sat - loglike), where loglike_sat is the
log-likelihood for the saturated model (a model with a free parameter per
observation). Null deviance is defined to be 2*(loglike_sat
-loglike(Null)); The NULL model refers to the intercept model, except for
the Cox, where it is the 0 model. Hence dev.ratio=1-deviance/nulldev, and
this deviance
method returns (1-dev.ratio)*nulldev.
Value
(1-dev.ratio)*nulldev
Author(s)
Jerome Friedman, Trevor Hastie and Rob Tibshirani
Maintainer:
Trevor Hastie hastie@stanford.edu
References
Friedman, J., Hastie, T. and Tibshirani, R. (2008) Regularization Paths for Generalized Linear Models via Coordinate Descent
See Also
glmnet
, predict
, print
, and coef
methods.
Examples
x = matrix(rnorm(100 * 20), 100, 20)
y = rnorm(100)
fit1 = glmnet(x, y)
deviance(fit1)