Snacks

Visualization Snacks are brief bits of visualization knowledge in written form. The idea is to put things into a form where you can get the main message quickly, and then refer to the details if you want.

A chart type is a bundle of encoding choices that someone found useful enough to name. Decomposing charts into their encodings explains why “line vs. bar” questions have answers, and shows you design choices (like ordering) that the chart names hide.

Airline Route Maps: An interesting Solution to a Node-Link Problem

Let’s look at the “Airline Route Maps” (the ones that are in the back of an airline magazine) as a way to explore the importance of task and how understanding task and data can lead to novel designs. It will show us a different way to think about node link diagrams more generally.

Core lesson: think about what a visualization makes easy to see. Different representations make some things easier, and harder. And be careful when dealing with geographic data in the US: populations and counties are spread unevenly.

This is a lesson on Axis Truncation for Line Graphs. It was inspired by a graph in the New York Times.

Don’t make the wrong thing easy to see. Here’s a real example from my own work where a seemingly innocent line graph was misleading and needed some serious redesign.

Line charts can be used (with caution) even when the X axis is neither interval nor continuous.

In this snack, we look at “value over time” graphs in two different iPhone apps. It’s a good opportunity to connect design and task with a comparative critique.

Snacks

Charts Are Just Encodings in Disguise

Airline Route Maps: An interesting Solution to a Node-Link Problem

Unemployment Changes Across The Country

College Attendance Line Chart

A Robot Performance Graph Mistake

Cairo Discrete Line

Phone App Time Graphs