working.comp: Internal Function
Description
It efficiently calculates the working model quantities needed to implement the automatic multiple smoothing parameter estimation
procedure by exploiting the band structure of the working linear model.References
Marra G. and Radice R. (2013), Estimation of a Regression Spline Sample Selection Model. Computational Statistics and Data Analysis, 61, 158-173.
Wojtys M., Marra G. and Radice R. (submitted), Copula Regression Spline Sample Selection Models: The R Package SemiParSampleSel.