# Describing GAM from ggplot's stat_smooth in a paper

I am writing a paper where I have some figures with lines drawn using ggplot2's stat_smooth with no arguments. When I generate a plot I get a warning saying that it is being fit with a GAM with formula y ~ s(x, bs = "cs")).

What I am wondering is: In writing a paper, how should I describe how this line was generated?

From the plotting output I've guessed that it is a "generalized additive model with cubic splines as a basis function". I don't really understand GAMs so I don't know if this is a comprehensible way to describe the model. The details of this model are not important for the paper; I am just using stat_smooth to draw a line in a figure and want to give it an informative caption.

• The references in the help (?gam:::s) describe these objects (smoothing splines) in some detail. See also the references in ?smooth.spline. Wikipedia gives a brief overview here, with some of the same references/readings. Dec 16, 2014 at 0:15