This function returns the smoothing matrix based on cubic smoothing spline method
Usage
ssmatls(n)
Arguments
n
the number of (equally spaced) grid
Value
A smoothing matrix based on smoothing spline method
Details
This function is based on Green and Silverman (1994) smoothing spline technique
References
Green, P. J., & Silverman, B. W. (1994). Nonparametric regression and generalized linear models: a roughness penalty approach (pp. 12-27). London: Chapman & Hall.