Book Image

Clojure Data Analysis Cookbook

By : Eric Rochester
Book Image

Clojure Data Analysis Cookbook

By: Eric Rochester

Overview of this book

<p>Data is everywhere and it's increasingly important to be able to gain insights that we can act on. Using Clojure for data analysis and collection, this book will show you how to gain fresh insights and perspectives from your data with an essential collection of practical, structured recipes.<br /><br />"The Clojure Data Analysis Cookbook" presents recipes for every stage of the data analysis process. Whether scraping data off a web page, performing data mining, or creating graphs for the web, this book has something for the task at hand.<br /><br />You'll learn how to acquire data, clean it up, and transform it into useful graphs which can then be analyzed and published to the Internet. Coverage includes advanced topics like processing data concurrently, applying powerful statistical techniques like Bayesian modelling, and even data mining algorithms such as K-means clustering, neural networks, and association rules.</p>
Table of Contents (18 chapters)
Clojure Data Analysis Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Differencing variables to show changes


Sometimes, we're more interested in how values change than we are in the values themselves. This information is latent in the data, but making it explicit makes it easier to work with and visualize.

Getting ready

First, we'll use the following dependencies in our project.clj file.

:dependencies [[org.clojure/clojure "1.4.0"]
               [incanter "1.4.1"]]

We also need to require Incanter in our script or REPL.

(require
  '[incanter.core :as i]
  'incanter.io)

Finally, we'll use the Virginia census data. You can download the file from http://www.ericrochester.com/clj-data-analysis/data/all_160_in_51.P3.csv.

(def data-file "data/all_160_in_51.P3.csv")

How to do it…

For this recipe, we'll take some census data and add a column to show the change in population between the 2000 and 2010 censuses.

  1. We need to read in the data.

    (def data (incanter.io/read-dataset data-file
    :header true))
  2. If we look at the values in the field for the year 2000 census population, some...