Predict.matrix
Prediction methods for smooth terms in a GAM
Description
Takes smooth
objects produced by smooth.construct
methods and obtains the matrix mapping the parameters associated with such a smooth to the predicted values of the smooth at a set of new covariate values.
In practice this method is often called via the wrapper function PredictMat
.
Usage
Predict.matrix(object,data) Predict.matrix2(object,data)
Arguments
object | is a smooth object produced by a |
data | A data frame containing the values of the (named) covariates at which the smooth term is to be evaluated. Exact requirements are as for |
.
Details
Smooth terms in a GAM formula are turned into smooth specification objects of class xx.smooth.spec
during processing of the formula. Each of these objects is converted to a smooth object using an appropriate smooth.construct
function. The Predict.matrix
functions are used to obtain the matrix that will map the parameters associated with a smooth term to the predicted values for the term at new covariate values.
Note that new smooth classes can be added by writing a new smooth.construct
method function and a corresponding Predict.matrix
method function: see the example code provided for smooth.construct
for details.
Value
A matrix which will map the parameters associated with the smooth to the vector of values of the smooth evaluated at the covariate values given in object
. If the smooth class is one which generates offsets the corresponding offset is returned as attribute "offset"
of the matrix.
Author(s)
Simon N. Wood [email protected]
References
Wood S.N. (2017) Generalized Additive Models: An Introduction with R (2nd edition). Chapman and Hall/CRC Press.
See Also
gam
,gamm
, smooth.construct
, PredictMat
Examples
# See smooth.construct examples
Copyright (©) 1999–2012 R Foundation for Statistical Computing.
Licensed under the GNU General Public License.