mrts {autoFRK} | R Documentation |
This function generates multi-resolution thin-plate spline basis functions. The basis functions are (descendingly) ordered in terms of their degrees of smoothness with a higher-order function corresponding to larger-scale features and a lower-order one corresponding to smaller-scale details. They are useful in the spatio-temporal random effects model.
mrts(knot, k, x = NULL, maxknot = 5000)
knot |
m by d matrix (d<=3) for m locations of d-dimensional knots as in ordinary splines. Missing values are not allowed. |
k |
the number (<=m) of basis functions. |
x |
n by d matrix of coordinates corresponding to n locations where the values of basis functions to be evaluated.
Default is |
maxknot |
maximum number of knots to be used in generating basis functions. If |
An mrts
object is generated. If x=NULL
(default) it returns
an m by k matrix of k basis function taken values at knots.
With x
given, it returns n by k matrix for basis functions taken values at x
.
ShengLi Tzeng and Hsin-Cheng Huang.
Tzeng, S., & Huang, H. C. (2018). Resolution Adaptive Fixed Rank Kriging. Technometrics, https://doi.org/10.1080/00401706.2017.1345701. Tzeng, S., & Huang, H. C. (2015). Multi-Resolution Spatial Random-Effects Models for Irregularly Spaced Data. arXiv preprint arXiv:1504.05659.
originalPar <- par(no.readonly = TRUE) knot <- seq(0, 1, l = 30) b <- mrts(knot, 30) x0 <- seq(0, 1, l = 200) bx <- predict(b, x0) par(mfrow = c(5, 6), mar = c(0, 0, 0, 0)) for (i in 1:30) { plot(bx[, i], type = "l", axes = FALSE) box() } par(originalPar)