Usability and Recall Evaluation of Virtual Reality Ontology Object Manipulation (VROOM) System.

Biomedical ontologies are repositories of knowledge that encapsulate biomedical terms and the relationships between them. When visualized, ontologies are complex graphs, where each node represents one biomedical concept, and links express binary relationships between pairs of concepts. Such a network can have thousands of nodes, making visualization and manipulation difficult. This paper presents a novel Virtual Reality Ontology Object Manipulation (VROOM) system that supports browsing and interaction with a biomedical ontology in a virtual 3-D space and a complementary usability evaluation of VROOM. VROOM provides editing tools such as scissors and a glue stick that can be used to reconnect concepts by direct manipulation. The study compares the recall process of information in a traditional 2-D ontology editor such as Prot´eg´e with the virtual reality setting. Our results show that virtual reality ontology manipulation is preferred over a more conventional graphical ontology browser on many usability aspects.