Hands-On Machine Learning with Scikit-Learn, Keras, and Tensorflow: Concepts, Tools, and Techniques to Build Intelligent Systems

by Aurélien Géron

As a result, all training instances lie within (or close to) a much lower-dimensional subspace of the high-dimensional space. This sounds very abstract, so let’s look at an example. In Figure 8-2 you can see a 3D dataset represented by circles.