integrateIspline {SCCS} | R Documentation |
Integral of I-splines
Description
Evaluates design matrix for integrals of I-splines and integrals of the integrals. The function evaluates first, second and third integrals of I-splines.
Usage
integrateIspline(x, knots1, m, int)
Arguments
x |
a numeric vector of values at which to evaluate the integrals of I-spline functions |
knots1 |
a numeric vector of interior knot positions with non-decreasing values |
m |
a positive integer giving the order of the spline function. |
int |
a positive integer (1, 2, or 3) for first, second or third integral of an I-spline function. |
Value
A matrix with length of (x) rows and length of (knots1) - m columns.
Author(s)
Yonas Ghebremichael-Weldeselassie, Heather Whitaker, Paddy Farrington.
References
Ghebremichael-Weldeselassie Y. (2014). Smooth risk functions for self-cotrolled case series models. PhD thesis, The Open University.
Ghebremichael-Weldeselassie, Y., Whitaker, H. J., Farrington, C. P. (2015). Spline-based self controlled case series method. Statistics in Medicine 33:639-649.