A reflection on seven years of the VAST challenge.

ABSTRACTWe describe the evolution of the IEEE Visual Analytics Science and Technology (VAST) Challenge from its origin in 2006 to present (2012). The VAST Challenge has provided an opportunity for visual analytics researchers to test their innovative thoughts on approaching problems in a wide range of subject domains against realistic datasets and problem scenarios. Over time, the Challenge has changed to correspond to the needs of researchers and users. We describe those changes and the impacts they have had on topics selected, data and questions offered, submissions received, and the Challenge format.