Book Image

Data Smart

By : John W. Foreman
Book Image

Data Smart

By: John W. Foreman

Overview of this book

Data Science gets thrown around in the press like it's magic. Major retailers are predicting everything from when their customers are pregnant to when they want a new pair of Chuck Taylors. It's a brave new world where seemingly meaningless data can be transformed into valuable insight to drive smart business decisions. But how does one exactly do data science? Do you have to hire one of these priests of the dark arts, the "data scientist," to extract this gold from your data? Nope. Data science is little more than using straight-forward steps to process raw data into actionable insight. And in Data Smart, author and data scientist John Foreman will show you how that's done within the familiar environment of a spreadsheet. Why a spreadsheet? It's comfortable! You get to look at the data every step of the way, building confidence as you learn the tricks of the trade. Plus, spreadsheets are a vendor-neutral place to learn data science without the hype. But don't let the Excel sheets fool you. This is a book for those serious about learning the analytic techniques, math and the magic, behind big data.
Table of Contents (18 chapters)
Free Chapter
1
Cover
2
Credits
3
About the Author
4
About the Technical Editors
5
Acknowledgments
18
End User License Agreement

Girls Dance with Girls, Boys Scratch their Elbows

The goal in k-means clustering is to take some points in space and put them into k groups (where k is any number you want to pick). Those k groups are each defined by a point in the center, kind of like a flag stuck in the moon that says, “Hey, this is the center of my group. Join me if you're closer to this flag than any others.” This group center (formally called the cluster centroid) is the mean from which k-means gets its name.

Take as an example a middle school dance. If you've blocked the horror of middle school dances from your mind, I apologize for resurfacing such painful memories.

Those in attendance at the McAcne Middle School dance, romantically called the “Under the Sea Gala,” are scattered about the floor as shown in Figure 2.1. I've even Photoshopped some parquet floor into the figure to help with the illusion.

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Figure 2.1 McAcne Middle School students tearing up the dance floor...