How to calculate the regularization parameter in linear regression

Question

When we have a high degree linear polynomial that is used to fit a set of points in a linear regression setup, to prevent overfitting, we use regularization, and we include

Answer 1

The cross validation described above is a method used often in Machine Learning. However, choosing a reliable and safe regularization parameter is still a very hot topic of research in mathematics. If you need some ideas (and have access to a decent university library) you can have a look at this paper: http://www.sciencedirect.com/science/article/pii/S0378475411000607