Collect information to smooth the term in its argument. Used in the model formula.
g(var, df = NULL)variable to be smoothed
equivalent degrees of freedom to be passed to the smoother. If NULL, smoothing parameter is selected by cross-validation
List containing the same elements of its argument.
This function only sets things up for model fitting. The smooth terms are actually fitted by bkfsmooth.
Green, P. J., Silverman, B. W. (1994) Nonparametric Regression and Generalized Linear Models: a roughness penalty approach. Chapman and Hall, London
Hastie, T. J., Tibshirani, R. J.(1990) Generalized Additive Models. Chapman and Hall, London
Junger, W. L. (2004) Semiparametric Poisson-Gamma models: a roughness penalty approach. MSc Dissertation. Rio de Janeiro, PUC-Rio, Department of Electrical Engineering.