d.matrix: Design matrix for splines

In thiyangt/fformpp: Feature-based FORecast Model Performance Prediction

Design matrix for splines

Description

Make a design matrix for multivariate thin plate splines and others.

Usage

d.matrix(x, knots, splineArgs)

Arguments

x	"matrix". the data to be used in the splines. You should *NOT* include a constant column. The intercept will be added automatically if required in "args".
knots	"list". knots locations for different spline components: knots$thinplate.a: "matrix" Knots for the additive part. knots$thinplate.s: "matrix" Knots for the surface part.
splineArgs	"list". Arguments list pass to the function, see bellow. splineArgs$comp: "character". The combination of splines, which can be "intercept": If included, will return design matrix with intercept. "covariates": If included, covariates should be included "thinplate.s": If included, the thinplate surface will be in; "thinplate.a": If include, the additive thinplate will be in. e.g. c("intercept", "covariates", "thinplate.s", "thinplate.a") means all the four components will be in the design matrix. splineArgs$thinplate.a.locate: "numeric", c(2, 3, 0) means 2 knots for first regressor, 3 knots for the second regressor and no knots for third regressor.

Details

The number of knots should be smaller than the number of observations.

Value

"matrix". The dimension depends on the arguments, and the first column is 1 as an intercept if required in "splineArgs".

Note

First version: Sun Mar 7 13:41:32 CET 2010. Current: Tue Dec 28 13:34:39 CET 2010.

Author(s)

Feng Li, Dept. of Statistics, Stockholm University, Sweden.

References

Denison et al (2002)

thiyangt/fformpp documentation built on Jan. 5, 2024, 5:44 a.m.