Definition
Polynomial Kernel Function
The polynomial kernel is very commonly used with support vector machines, which you will learn about in the next video. It can be used for image processing, but the RBF kernel is usually the better choice here. Another good application for the polynomial kernel is the field of natural language processing. A common choice is a degree of as larger degrees tend to overfit any tasks in the area of NLP. The polynomial kernel is defined as:
k(x_{i}, y_{i}) = (x_{i}^T x_{j} + c)^d, \quad \text{where } d \text{ is the degree and } $c \geq 0$