Unsupervised learning

In this section, we will provide a brief introduction to unsupervised machine learning technique with appropriate examples. Let's start the discussion with a practical example. Suppose you have a large collection of not-pirated-totally-legal mp3s in a crowded and massive folder on your hard drive. Now, what if you can build a predictive model that helps automatically group together similar songs and organize them into your favorite categories such as country, rap, rock, and so on. This act of assigning an item to a group such that a mp3 to is added to the respective playlist in an unsupervised way. In the previous chapters, we assumed you're given a training dataset of correctly labeled data. Unfortunately, we don't always have that extravagance when we collect data in the real-world. For example, suppose we would like to divide up a large...