Recent Posts

Using CartoDB to visualize the relationship between private prisons and incarceration rates

7 minute read , Posted on April 17, 2017, by Carl V. Lewis

The last post I wrote about CartoDB used the CartoDB API and Leaflet.js to produce a hover tooltip map of census data. Looking back, while it’s quite useful to learn CartoDB’s API, it’s now possible to achieve those same visual cues and interactivity without spending time wading through complex, undocumented JavaScript.

What we can learn about charts from The WSJ Guide to Information Graphics

12 minute read , Posted on July 13, 2012, by Carl V. Lewis

Although geared primarily toward the production of static graphics for print publications, Dona M. Wong’s The Wall Street Journal Guide to Information Graphics (2010) provides a wealth of salient and time-honored tips and guidelines that any student of data visualization would be well-advised to follow. At the heart of Wong’s book is the notion that data integrity trumps all else, and no matter how aesthetically pleasing or visually powerful an information graphic may be, if it doesn’t communicate clear...

Making the case for hover interactions in maps

19 minute read , Posted on July 12, 2012, by Carl V. Lewis

In keeping with my recent spate of mapping nerdiness, I decided to take an interactive map I produced last month displaying statewide annual population changes a step further by adding mouseover/hover capabilities. Here’s the hover-y, nicely-colored chloropleth map I came up with. But before I get into the nitty-gritty of how I created the map –– which I’ll explain step-by-step in a later post –– let me exercise a bit of self-indulgence by defending my...

Using data-viz to make a wire story stand out from the pack

13 minute read , Posted on May 06, 2012, by Carl V. Lewis

I’ve been interested lately in finding examples of online-only, collaborative, non-profit newsrooms who’ve utilized the power of data visualization techniques to give added value to stories that otherwise wouldn’t necessarily be unique, and in doing so beat out legacy news organizations who published a text narrative alone. Take, for example, this data-rich story and interactive map displaying statewide testing results published by NJSpotlight Friday. While the news that only 8 out of 10 graduating seniors had passed New Jersey’s current...

Overlaying a bubble chart onto a Google map

25 minute read , Posted on May 04, 2012, by Carl V. Lewis

Others may hate, but I’m a big fan of using bubbles to display data. When implemented correctly (i.e. scaled in terms of area instead of diameter), bubbles can be an aesthetically appealing and concise way to represent the value of data points in an inherently visual format. Bubbles are even more useful when they include interactivity, with events like mouseover and zoom allowing users to drill down and compare similar-sized bubbles more easily than they...

On Richard Boarman’s “Bubble Trees: The Visualization of Hierarchical Structure”

3 minute read , Posted on April 06, 2012, by Carl V. Lewis

In his brief two-page paper “Bubble Trees: The Visualization of Hierarchical Structure,” Richard Boardman proposes a new type of interactive presentation of hierarchical data that he calls the bubble tree. To bolster his argument, Boardman points out the difficulties inherent in the traditional “tree” structure, which suffers from the “breadth versus depth” problem by leading to information overload and taking up too much screen real estate. As a solution, he proposes a clickable bubble tree that leads to child...

Critique, “French wine map shows the best vintage, from 1978 to 2011”

4 minute read , Posted on April 01, 2012, by Carl V. Lewis

It’s nearing the end of the week, so what better way to relax than with a good bottle of wine and some leisure reading? Problem is, I’m not very skilled at buying wine that tastes any good. I always end up paying more for the bitter, expensive stuff. Fortunately,  there’s a pretty cool news app for that. The Telegraph UK’s recent interactive app on French wine ratings allows users to browse through the years to see...

Should data viz be a specialty or a commodity skill in the newsroom?

8 minute read , Posted on April 01, 2012, by Carl V. Lewis

An interesting question came up at last Wednesday’s Doing Data Journalism (#doingdataj) panel hosted by the Tow Center for Digital Journalism here at Columbia’s J-School: Should there be data specialists in the newsroom, or can everyone be a data journalist? For New York Times interactive editor Aron Pilholfer, who participated in the panel, the question is not so much should everyone do data as will everyone do data. And for Pilholfer, the answer to that question clearly...

Aron Pilholfer at #doingdataj

less than 1 minute read , Posted on April 01, 2012, by Carl V. Lewis

Totally agree, but harbor the lurking suspicion that many traditional readers still like to read pretty narratives and don’t care as much if the facts back them up. In other words, it’s an audience problem just as much as it is an editorial one.