Davy Cielen - Introducing Data Science: Big Data, Machine Learning, and more, using Python tools

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Development editor: Dan MaharryTechnical development editors: Michael Roberts, Jonathan ThomsCopyeditor: Katie PetitoProofreader: Alyson BrenerTechnical proofreader: Ravishankar RajagopalanTypesetter: Dennis DalinnikCover designer: Marija Tudor

ISBN 9781633430037

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Its in all of us. Data science is what makes us humans what we are today. No, not the computer-driven data science this book will introduce you to, but the ability of our brains to see connections, draw conclusions from facts, and learn from our past experiences. More so than any other species on the planet, we depend on our brains for survival; we went all-in on these features to earn our place in nature. That strategy has worked out for us so far, and were unlikely to change it in the near future.

But our brains can only take us so far when it comes to raw computing. Our biology cant keep up with the amounts of data we can capture now and with the extent of our curiosity. So we turn to machines to do part of the work for us: to recognize patterns, create connections, and supply us with answers to our numerous questions.

The quest for knowledge is in our genes. Relying on computers to do part of the job for us is notbut it is our destiny.

A big thank you to all the people of Manning involved in the process of making this book for guiding us all the way through.

Our thanks also go to Ravishankar Rajagopalan for giving the manuscript a full technical proofread, and to Jonathan Thoms and Michael Roberts for their expert comments. There were many other reviewers who provided invaluable feedback throughout the process: Alvin Raj, Arthur Zubarev, Bill Martschenko, Craig Smith, Filip Pravica, Hamideh Iraj, Heather Campbell, Hector Cuesta, Ian Stirk, Jeff Smith, Joel Kotarski, Jonathan Sharley, Jrn Dinkla, Marius Butuc, Matt R. Cole, Matthew Heck, Meredith Godar, Rob Agle, Scott Chaussee, and Steve Rogers.

First and foremost I want to thank my wife Filipa for being my inspiration and motivation to beat all difficulties and for always standing beside me throughout my career and the writing of this book. She has provided me the necessary time to pursue my goals and ambition, and shouldered all the burdens of taking care of our little daughter in my absence. I dedicate this book to her and really appreciate all the sacrifices she has made in order to build and maintain our little family.

I also want to thank my daughter Eva, and my son to be born, who give me a great sense of joy and keep me smiling. They are the best gifts that God ever gave to my life and also the best children a dad could hope for: fun, loving, and always a joy to be with.

A special thank you goes to my parents for their support over the years. Without the endless love and encouragement from my family, I would not have been able to finish this book and continue the journey of achieving my goals in life.

Id really like to thank all my coworkers in my company, especially Mo and Arno, for all the adventures we have been through together. Mo and Arno have provided me excellent support and advice. I appreciate all of their time and effort in making this book complete. They are great people, and without them, this book may not have been written.

Finally, a sincere thank you to my friends who support me and understand that I do not have much time but I still count on the love and support they have given me throughout my career and the development of this book.

D AVY C IELEN

I would like to give thanks to my family and friends who have supported me all the way through the process of writing this book. It has not always been easy to stay at home writing, while I could be out discovering new things. I want to give very special thanks to my parents, my brother Jago, and my girlfriend Delphine for always being there for me, regardless of what crazy plans I come up with and execute.

I would also like to thank my godmother, and my godfather whose current struggle with cancer puts everything in life into perspective again.

Thanks also go to my friends for buying me beer to distract me from my work and to Delphines parents, her brother Karel, and his soon-to-be wife Tess for their hospitality (and for stuffing me with good food).

All of them have made a great contribution to a wonderful life so far.

Last but not least, I would like to thank my coauthor Mo, my ERC-homie, and my coauthor Davy for their insightful contributions to this book. I share the ups and downs of being an entrepreneur and data scientist with both of them on a daily basis. It has been a great trip so far. Lets hope there are many more days to come.

A RNO D. B. M EYSMAN

First and foremost, I would like to thank my fiance Muhuba for her love, understanding, caring, and patience. Finally, I owe much to Davy and Arno for having fun and for making an entrepreneurial dream come true. Their unfailing dedication has been a vital resource for the realization of this book.

M OHAMED A LI

I can only show you the door. Youre the one that has to walk through it.

Morpheus, The Matrix

Welcome to the book! When reading the table of contents, you probably noticed the diversity of the topics were about to cover. The goal of Introducing Data Science is to provide you with a little bit of everythingenough to get you started. Data science is a very wide field, so wide indeed that a book ten times the size of this one wouldnt be able to cover it all. For each chapter, we picked a different aspect we find interesting. Some hard decisions had to be made to keep this book from collapsing your bookshelf!

We hope it serves as an entry pointyour doorway into the exciting world of data science.