Vectors, dimensions and feature spaces

If you strip machine learning of all the fancy words and buzzwords, in the end you almost always end up with the same idea: we represent real-world objects with numbers and work with those numbers mathematically. This is where vectors, dimensions, and feature spaces come onto the stage. As PHP developers, it is especially important for you to understand this intuitively rather than formally, because in code you will constantly deal not with abstract linear algebra, but with arrays of numbers, matrices, and operations on them.

• Vector dimension
• Normalization
• Standardization
• Categorical features and dimensionality
• Connection to specific algorithms