Luderschmidt, JohannesDörner, RalfSeyer, MelanieFrieß, FredericHeimann, RudiReiterer, HaraldDeussen, Oliver2017-11-222017-11-222012978-3-486-71879-9https://dl.gi.de/handle/20.500.12116/7801Vispol (Visualization for the police) is an interactive graph-based visualization that supports the work of the police of Hessen, Germany. A Vispol graph visualizes involved persons and their relations in crisis incidents like hostage takings or bank hold-ups. It presents a tabletop-based multi-touch and tangible user interface for the structured creation and manipulation of node-link diagrams. For instance, persons can be stamped into a graph with a stamp tangible object and links can be established employing multi-touch gestures. The graph can be visually filtered by applying layout algorithms via layout tangibles or by using a tangible magnet metaphor. We presented Vispol to the police to gather qualitative feedback. The police appreciated the visualization and generally liked the approach to use a multi-touch and tangible user interface. However, when it came to interacting with the tabletop system, police officers acted very cautiously and hesitatingly, as they were afraid of the new technology.enMulti-TouchTangible User InterfacesInformation VisualizationGraphsSafety Critical ApplicationText/Conference Paper