Core Design Principles for Displaying Quantitative Information from Stephen Few (data display god!). Downloadable pdf.
These form the basis of a presentation given by Juice Analytics on the six principles of visual context:
* Principle of Proximity – Things that are visually close to each other are related
* Principle of Similarity – Things that look like each other (size, color, shape) are related
* Principle of Enclosure – Things that are enclosed by a shape are related
* Principle of Closure – We see incomplete shapes as complete
* Principle of Continuity – Things that are aligned are related
* Principle of Connection – Things that are visually connected are related
Learn more about JA via their post and site at http://www.juiceanalytics.com/writing/tableau-stephen-few-and-six-principles/ and the few pdf is definitely must-read content.
Idea: Guidelines for stakeholder-focused evaluation graphics