Learn R Programming

gelnet (version 1.2.1)

gelnet.krr: Kernel ridge regression

Description

Learns a kernel ridge regression model.

Usage

gelnet.krr(K, y, a, lambda, fix.bias = FALSE)

Arguments

K
n-by-n matrix of pairwise kernel values over a set of n samples
y
n-by-1 vector of response values
a
n-by-1 vector of samples weights
lambda
scalar, regularization parameter
fix.bias
set to TRUE to force the bias term to 0 (default: FALSE)

Value

  • A list with two elements: [object Object],[object Object]

Details

The entries in the kernel matrix K can be interpreted as dot products in some feature space $\phi$. The corresponding weight vector can be retrieved via $w = \sum_i v_i \phi(x_i)$. However, new samples can be classified without explicit access to the underlying feature space: $$w^T \phi(x) + b = \sum_i v_i \phi^T (x_i) \phi(x) + b = \sum_i v_i K( x_i, x ) + b$$

See Also

gelnet.lin