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This article was adapted from a section of the Data Journalism Handbook, written by David Suda. You can view the complete work here.
If you spend any time online, you're probably all too familiar with infographics, those ubiquitous, graphic representations of data. The reason we're drawn to them is hardly a mystery: We're visual creatures. Infographics can be funny, informative, even beautiful. And some truly illuminate a topic in a way we'd never imagined. Like a in a way that can help forge new discoveries in cancer research. Or help scientists discover new plantets. Or maybe just create some social commentary about how many Starbucks locations are in the United States – or how few female senators.
So we started wondering about all the ways that data can be used in design. Here are a few key examples where data visualization really shines – and some key instances when it's likely to fall short.
To Show Hierarchy
Source: OpenSpending.org
In 1991, researcher Ben Shneiderman invented a new visualization form called the "treemap" consisting of multiple boxes concentrically nested inside of each other. The area of a given box represents the quantity it represents, both in itself and as an aggregate of its contents. Whether visualizing a national budget by agency and sub agency, visualizing the stock market by sector and company, or a programming language by classes and sub-classes, the treemap is a compact and intuitive interface for mapping an entity and its constituent parts. Another effective format is the dendrogram, which looks like a more typical organization chart, where sub-categories continue to branch off a single originating trunk.
To Browse Large Databases
Every death on the road in Great Britain, 1999-2000
Source: BBC
While sometimes data visualization is very effective at taking familiar information and showing it in a whole new light, what happens when you have brand-new information that people want to navigate? The age of data brings with it startling new discoveries almost every day, from Eric Fischer’s brilliant geographic analysis of Flickr snapshots to the Wall Street's Journal's analysis of New York City’s release of thousands of previously confidential teacher evaluations.
These data sets are at their most powerful when users can dig in and drill down to the information that is most relevant to them.
In early 2010, The New York Times was given access to Netflix’s normally private records of what areas rent which movies the most often. While Netflix declined to disclose raw numbers, The Times created an engaging interactive database that let users browse the top 100-ranked rentals in 12 U.S. metro areas, broken down to the postal code level. A colour-graded heatmap overlaid on each community enabled users to quickly scan and see where a particular title was most popular.
Toward the end of that same year, the Times published the results of the United States decennial census – just hours after it was released. The interface, built in Adobe Flash, offered a number of visualization options and allowed users to browse down to every single census block in the nation (out of 8.2 million) to see the distribution of residents by race, income and education. Such was the resolution of the data, when looking through the data set in the first hours after publication, you wondered if you might be the first person in the world to explore that corner of the database.
Similar laudable uses of visualization as a database front-end include the BBC’s investigation of traffic deaths (shown in the image above), and many of the attempts to quickly index large scale data dumps as Wikileaks' release of the Iraq and Afghanistan war logs.
To Envision Alternate Outcomes
Budget forecasts compared with reality
Source: New York Times
In the New York Times, Amanda Cox’s 2010 "porcupine chart" of tragically optimistic U.S. deficit projections over the years shows how sometimes what happened is less interesting than what didn’t happen. Cox’s fever line showing the surging budget deficit after a decade of war and tax breaks shows how unrealistic expectations of the future can turn out to be.
Bret Victor, a longtime Apple interface designer (and originator of the "kill math" theory of visualization to communicate quantitative information), has prototyped a kind of reactive document. In his example, energy conservation ideas include editable premises, whereby a simple step like shutting off lights in empty rooms could save Americans the output of from two to 40 coal plants. Changing the percentage referenced in the middle of a paragraph of text causes the text in the rest of the page to update accordingly!
When Data Visualization Works
In the end, effective data visualization depends on good, clean, accurate and meaningful information. Whether that information is being used in the news, in marketing, in businesses, to advance science, or in one of the many unfathomable ways it will undoubtedly be used in the future, visualization can be a more effective and interactive way to communicate data that would otherwise be dry, lifeless, incomprehensible. When displayed visually, data can be transformed from a raw, unassimilable material to something that feeds our minds – and our visual senses. In other words, it provides a whole new way not just of looking at data, but of looking at the world.
Have you seen any interesting data visualization projects? Let us know. We'd love to write about them.
The Data Journalism Handbook, and this adaptation, can be freely copied, redistributed and reused under the terms of the Creative Commons Attribution-ShareAlike license.
