SGD classification with hinge loss

In Chapter 4, Logistic Regression we explored a classifier based on a regressor, logistic regression. Its goal was to fit the best probabilistic function associated with the probability of one point to be classified with a label. Now, the core function of the algorithm considers all the training points of the dataset: what if it's only built on the boundary ones? That's exactly the case with the linear Support Vector Machine (SVM) classifier, where a linear decision plane is drawn by only considering the points close to the separation boundary itself.

Beyond working on the support vectors (the closest points to the boundary), SVM uses a new decision loss, called hinge. Here's its formulation:

Where t is the intended ...

Get Regression Analysis with Python now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.