Support Vector Machines (SVM) are powerful supervised learning models used for classification and regression. In this post, we’ll break down the geometry and logic behind them.
The Goal: Finding the Best Boundary
Imagine you have two groups of data points on a 2D graph. You want to draw a line that separates them. There are many lines you could draw, but which one is the “best”?
Hyperplanes 🔎
In SVM, the boundary that separates the data is called a Hyperplane. * In 2D, a hyperplane is a 1D line. * In 3D, a hyperplane is a 2D plane. * In N dimensions, a hyperplane has N-1 dimensions.
Margin and Support Vectors 🚂
SVM doesn’t just find any line; it finds the one with the Maximum Margin.
- Support Vectors: These are the data points from each class that are closest to the boundary. They “support” the hyperplane.
- Margin: The distance between the hyperplane and the support vectors.
The goal of SVM is to maximize this margin. A wider margin acts like a “safety buffer,” making the model more robust to new, slightly different data.
The Kernel Trick 🚂
What if the data isn’t linearly separable? Imagine a ring of “Type A” points surrounding a circle of “Type B” points. No straight line can separate them.
SVM solves this using the Kernel Trick. It mathematically transforms the data from a lower dimension to a higher dimension where a flat hyperplane can separate them.
Think of it like lifting the “Type B” points off the table into the air; now you can slide a sheet of paper (a plane) between them and the “Type A” points on the table.
Summary
- SVM looks for the widest possible “street” between classes.
- Support Vectors are the most important points that define that street.
- The Kernel Trick allows SVM to solve complex, non-linear problems.
Exercise
Research these terms to see the math behind SVM: 1. Lagrange Multipliers 2. Platt’s SMO Algorithm (The standard algorithm for training SVMs)
Next, we move into the world of Neural Networks—the foundation of modern AI.
Written by
Abdur-Rahmaan Janhangeer
Chef
Python author of 7+ years having worked for Python companies around the world
Suggested Posts
Logistic Regression vs. K Nearest Neighbors in Machine Learning
In machine learning, using an appropriate algorithm according to the behavior of the data and its pa...
Linear Regression vs. Decision Trees vs. Support Vector Machines
Machine Learning algorithms are one of the most important things to decide during model training and...
Machine Learning Part 9: An Introduction to Neural Networks
Neural Networks are the backbone of modern Artificial Intelligence, powering everything from face re...