“It ain't so much the things we don't know that get us into trouble. It's the things we know that just ain't so.”
Josh Billings, Humorist
This book isn't really about data analysis and visualization.
Yes, almost every section is focused on those topics, but being able to perform good data analysis and produce informative visualizations is just a means to an end. You never (okay, rarely) analyze data for the sheer joy of analyzing data. You analyze data and create visualizations to gain new perspectives, to find relationships you didn't know existed, or to simply discover new information. In short, you do data analysis and visualizations to learn, and that is what this book is about. You want to learn how your information systems are functioning, or more importantly how they are failing and what you can do to fix them.
The cyber world is just too large, has too many components, and has grown far too complex to simply rely on intuition. Only by augmenting and supporting your natural intuition with the science of data analysis will you be able to maintain and protect an ever-growing and increasingly complex infrastructure. We are not advocating replacing people with algorithms; we are advocating arming people with algorithms so that they can learn more and do a better job. The data contains information, and you can learn better with the information in the data than without it.
This book focuses on using real data—the types of data you ...