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
.
Predict.matrix(object,data)
Predict.matrix2(object,data)
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.
is a smooth object produced by a smooth.construct
method function. The object
contains all the information required to specify the basis for a term of its class, and this information is
used by the appropriate Predict.matrix
function to produce a prediction matrix for new covariate values.
Further details are given in smooth.construct
.
A data frame containing the values of the (named) covariates at which the smooth term is to be
evaluated. Exact requirements are as for smooth.construct
and smooth.construct2
.
Simon N. Wood simon.wood@r-project.org
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.
Wood S.N. (2017) Generalized Additive Models: An Introduction with R (2nd edition). Chapman and Hall/CRC Press.
gam
,gamm
,
smooth.construct
, PredictMat
# See smooth.construct examples
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