Book Image

Principles of Data Science - Second Edition

By : Sinan Ozdemir, Sunil Kakade, Marco Tibaldeschi
Book Image

Principles of Data Science - Second Edition

By: Sinan Ozdemir, Sunil Kakade, Marco Tibaldeschi

Overview of this book

Need to turn programming skills into effective data science skills? This book helps you connect mathematics, programming, and business analysis. You’ll feel confident asking—and answering—complex, sophisticated questions of your data, making abstract and raw statistics into actionable ideas. Going through the data science pipeline, you'll clean and prepare data and learn effective data mining strategies and techniques to gain a comprehensive view of how the data science puzzle fits together. You’ll learn fundamentals of computational mathematics and statistics and pseudo-code used by data scientists and analysts. You’ll learn machine learning, discovering statistical models that help control and navigate even the densest datasets, and learn powerful visualizations that communicate what your data means.
Table of Contents (17 chapters)
16
Index

Basic symbols and terminology

In the following section, we will review the mathematical concepts of vectors, matrices, arithmetic symbols, and linear algebra, as well as some more subtle notations that are used by data scientists.

Vectors and matrices

A vector is defined as an object with both magnitude and direction. This definition, however, is a bit complicated. For our purpose, a vector is simply a 1-dimensional array representing a series of numbers. Put another way, a vector is a list of numbers.

It is generally represented using an arrow or bold font, as follows:

Vectors and matrices

Vectors are broken into components, which are individual members of the vector. We use index notations to denote the element that we are referring to, as follows:

Vectors and matrices

Note

In math, we generally refer to the first element as index 1, as opposed to computer science, where we generally refer to the first element as index 0. It is important to remember which index system you are using.

In Python, we can represent arrays in many ways. We...