lm.ridge
From MASS v7.3-47
by Brian Ripley
Fit a linear model by ridge regression.
- Keywords
- models
Usage
lm.ridge(formula, data, subset, na.action, lambda = 0, model = FALSE,
x = FALSE, y = FALSE, contrasts = NULL, …)
Arguments
- formula
-
a formula expression as for regression models, of the form
response ~ predictors
. See the documentation offormula
for other details.offset
terms are allowed. - data
-
an optional data frame in which to interpret the variables occurring
in
formula
. - subset
- expression saying which subset of the rows of the data should be used in the fit. All observations are included by default.
- na.action
- a function to filter missing data.
- lambda
- A scalar or vector of ridge constants.
- model
- should the model frame be returned? Not implemented.
- x
- should the design matrix be returned? Not implemented.
- y
- should the response be returned? Not implemented.
- contrasts
-
a list of contrasts to be used for some or all of factor terms in the
formula. See the
contrasts.arg
ofmodel.matrix.default
. - …
-
additional arguments to
lm.fit
.
Details
If an intercept is present in the model, its coefficient is not penalized. (If you want to penalize an intercept, put in your own constant term and remove the intercept.)
Value
A list with components
lambda
.
Note that these are not on the original scale and are for use by the
coef
method.
y
x
matrix
References
Brown, P. J. (1994) Measurement, Regression and Calibration Oxford.
See Also
Examples
library(MASS)
longley # not the same as the S-PLUS dataset
names(longley)[1] <- "y"
lm.ridge(y ~ ., longley)
plot(lm.ridge(y ~ ., longley,
lambda = seq(0,0.1,0.001)))
select(lm.ridge(y ~ ., longley,
lambda = seq(0,0.1,0.0001)))
Community examples
Looks like there are no examples yet.