A Data-centric History of U.S. Coins

eBay Data Viz screen cap

A Data-centric His­tory of U.S. Coins

(Requires a WebGL enabled browser like Chrome)

I’d like to show off my data visu­al­iza­tion project I worked on through an eBay spon­sored class at UCSC. The class was focused on user expe­ri­ence and the web, so we exper­i­mented with three.js (WebGL), jQuery, and eBay javascript API. I chose to dis­play US coin data from used coin sales on eBay.

With the eBay API, it’s easy to dis­play live data. But that func­tion­al­ity is lim­ited by a cap on queries per day. I wanted to use a lot of data to limit the amount of dis­crep­an­cies. My biggest task was to make a ton of queries offline, sort through the data (a total of 50Mb of JSON text data), and out­put it as less than 150Kb of JSON so that users can eas­ily access much more data than they could through eBay live data. I wrote an algo­rithm which gath­ers all the coin queries, sorts them by year, then aver­ages the cost per year and out­puts a much more com­pact data struc­ture in JSON. This allowed my site to visu­al­ize over 230,000 data points, as opposed to only ~5000 per day of live data. I could then cat­e­go­rize, orga­nize, and dis­play mul­ti­di­men­sional data in less space, a goal of data visu­al­iza­tion accord­ing to Edward Tufte.

I’m now really inter­ested in the poten­tial of data visu­al­iza­tion and look­ing for ways to use my skills in the world, espe­cially apply­ing them to other fields and dis­courses. Let me know if you have ques­tions about my code or want to use in any way.

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>