Micire, M., Schedlbauer, M., Yanco, H. Horizontal Selection Proceedings of the Thirteenth Americas Conference on Information Systems, Keystone, Colorado August 09 th -12 th 2007 Horizontal Selection: An Evaluation of a Digital Tabletop Input Device Mark Micire, Martin Schedlbauer, Holly Yanco University of Massachusetts Lowell Lowell, MA 01854 (USA) {mmicire,mschedlb,holly}@cs.uml.edu Abstract Recent advances in digital tabletop touch-and-gesture-activated screens have allowed for small group collaboration. The newest generation screens simultaneously support multiple users, multiple contact points per user, and gesture recognition. Although the usefulness and potential of these devices has been demonstrated, a formal quantitative evaluation of their performance has not been performed to date. This paper investigates the performance characteristics of a front-projected, 1:1 perspective, touch interface in consideration of Fitts’ law. Specifically, this study evaluates the Mitsubishi Electric Research Laboratories’ (MERL) DiamondTouch digital tabletop. This paper explores the hypothesis that selection is faster and more accurate on horizontal digital tabletops compared to a mouse. Keywords Fitts’ law, tabletop, human performance modeling, input device evaluation, Mitsubishi DiamondTouch. Motivation Hurricane Katrina made landfall near Biloxi, Mississippi in late August 2005. The resulting disaster response revealed a large technological gap. Although satellite and aerial information existed, it was not used by search teams. Instead, during the night, US Geological Survey and state forestry personnel manually updated area maps based on verbal search reports. These maps were distributed to search personnel in the morning for the daily grid searches. When the teams returned that evening, updates were manually integrated by USGS and forestry personnel. Multi-touch screens may be able to bridge the gap between the unused aerial reconnaissance information and the rescue teams on the ground. Once information on the disaster is registered to a virtual map, the command staff can quickly and interactively assess the situation. Multiple representatives from multiple agencies can have the convenience of a paper tabletop map while benefiting from the dynamic nature of this digital medium. There are many places that a digital command and control interface can help in a disaster relief effort. Before and after comparisons of the area can be valuable to the command staff. Remaining structures can be annotated to indicate future search areas. Debris fields can be marked as a secondary search priority. The relocation of maritime structures and large boats may also be noted. Overall, the search space can be optimized and high priority given to areas with greatest potential for survivors. We envision an intelligent command and control interface that coalesces available information, e.g. combining satellite and aerial data over time with city planning layouts (street, sewer, water, gas, electric, and communication). When informed decision on the search priorities occurs, then the new maps can be simply printed and distributed to the rescuers in the field. An enabling technology being evaluated for this purpose is the Mitsubishi DiamondTouch. Mitsubishi Electric Research Laboratories have created a touch-screen that breaks the normal monitor-keyboard-mouse paradigm. The DiamondTouch is capable of uniquely identifying multiple users simultaneously by touch. The board itself is embedded with antennas in the horizontal and vertical directions, which form a grid. The antennas continuously transmit signals. When a user touches the