Support Vector Machines Part 2: Exploring the Polynomial Kernel

Welcome to another exciting journey through the world of support vector machines! In this installment, we will dive into the intricacies of the polynomial kernel and uncover its parameters and how it calculates high-dimensional relationships. If you’re already familiar with support vector machines, this quest will expand your knowledge even further. But if you’re new to this topic, don’t worry! We’ll provide you with the necessary background information along the way.

Support Vector Machines Part 2: Exploring the Polynomial Kernel
Support Vector Machines Part 2: Exploring the Polynomial Kernel

Understanding the Polynomial Kernel

Imagine a dataset with drug dosages measured in a group of patients. Some patients were cured (represented by green dots) while others were not (represented by red dots). Our goal is to find a support vector classifier that can accurately separate the two groups.

However, due to the considerable overlap between the cured and uncured patients, it proves challenging to find a satisfactory solution using a traditional support vector classifier.

But fear not! We can leverage the power of the polynomial kernel to transform our data and discover hidden patterns that were not apparent in the original dataset.

Exploring the Polynomial Kernel Parameters

The polynomial kernel equation looks like this:

K(a, b) = (a • b + c)^d
  • a and b are different observations in the dataset.
  • c determines the coefficient of the polynomial.
  • d represents the degree of the polynomial.

In our example, we set c to 1/2 and d to 2. By squaring the term, we can expand it into the product of two terms and perform the multiplication.

Further reading:  Gradient Boost: Regression Main Ideas

Now, let’s take a closer look at the resulting polynomial equation:

K(a, b) = (a • b + 1/2)^2 = a^2 • b^2 + a • b + 1/4

When we calculate the dot product, we multiply the corresponding terms together and add them up. This process provides us with the high-dimensional coordinates for our data. The first terms correspond to the x-axis coordinates, the second terms to the y-axis coordinates, and the third terms to the z-axis coordinates. However, since the z-axis coordinates are the same for both points, we can disregard them.

Unveiling Hidden Relationships

By employing the polynomial kernel, we can now determine the high-dimensional relationships between pairs of observations without actually transforming the data to a higher dimension.

To do this, we simply calculate the dot product between each pair of points using the polynomial kernel equation. For example, if we want to find the high-dimensional relationship between two specific observations, we plug in the dosage values into the kernel equation and perform the calculation.

The resulting value, such as 16,002.25, is one of the two-dimensional relationships that we need to solve for the support vector classifier. Amazingly, we achieve this without transforming the data into two dimensions!

FAQs

Q1: Why is the polynomial kernel useful in support vector machines?

The polynomial kernel allows us to capture complex relationships between observations by transforming the data into a higher-dimensional space. This transformation uncovers hidden patterns that are not visible in the original dataset.

Q2: How do we determine the values for c and d?

The values for c and d are typically determined using cross-validation techniques. This ensures that the polynomial kernel maximizes the accuracy of the support vector classifier.

Further reading:  Recurrent Neural Networks (RNNs) - A Guide to Understanding and Using Them

Conclusion

Congratulations! You have successfully explored the fascinating world of the polynomial kernel in support vector machines. By understanding its parameters and how it calculates high-dimensional relationships, you are now equipped with a powerful tool to solve complex classification problems.

If you want to continue your quest for knowledge in the field of technology, remember to check out Techal, where you’ll find more insightful articles and guides to empower you in the ever-evolving world of technology. Happy learning!

YouTube video
Support Vector Machines Part 2: Exploring the Polynomial Kernel