A covariance function object of class 'kernel_polynomial'.
Arguments
variance
Variance parameter \(\sigma^2\) (default 1).
offset
Offset parameter \(c\) (default 0).
degree
Polynomial degree \(p\) (default 2).
Details
The polynomial covariance function produces sample paths that are
polynomial functions of degree at most degree. Setting
degree = 1 and offset = 0 gives the linear kernel.