''Imagine you are a member of a design team located in Calgary. You schedule a brainstorming session with your Vancouver-based counterparts on a new product idea. Your company has special meeting rooms in each city, connected by audio links and containing large digital stylus-based whiteboard displays. Groupware allows members of your Calgary team and the Vancouver team to concurrently draw ideas on the display wall using styli, which everyone sees in real time.''
''Mixed Presence Groupware'' is software that realizes these scenarios, connecting distributed ''teams'' together while allowing collocated participants to interact through the system.
VideoArms: Addressing Presence Disparity
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Mixed Presence Groupware (MPG) supports both co-located and distributed participants working over a shared visual workspace. It does this by connecting multiple single-display groupware workspaces together through a shared data structure. Our implementation and observations of MPG systems exposes two problems. The first is display disparity, where connecting heterogeneous tabletop and vertical displays introduces issues in how one seats people around the virtual table and how one orients work artifacts. The second is presence disparity, where a participant's perception of the presence of others is markedly different depending on whether a collaborator is co-located or remote. This is likely caused by inadequate consequential communication between remote participants, which in turn disrupts group collaborative and communication dynamics. To mitigate display and presence disparity problems, we determine virtual seating positions and replace conventional telepointers with digital arm shadows that extend from a person's side of the table to their pointer location.
Tang, A. and Greenberg, S. (2005). Supporting Awareness in Mixed Presence Groupware. ACM CHI 2005 Workshop on Awareness systems: Known Results, Theory, Concepts and Future Challenges. Organized by Markopoulos, P., de Ruyter, B., and Mackay, W. April. (workshop) Tang, A., Neustaedter, C. and Greenberg, S. (2004). VideoArms: Supporting Remote Embodiment in Groupware. (Google video) Video Proceedings of the ACM CSCW Conference on Computer Supported Cooperative Work. (November 6-10, Chicago, Illinois). ACM Press. Video and abstract, duration 5:20. (conference) |
Understanding Mixed Presence Groupware
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Mixed Presence Groupware (MPG) supports both co-located and distributed participants working over a shared visual workspace. It does this by connecting multiple single-display groupware workspaces together through a shared data structure. Our implementation and observations of MPG systems exposes two problems. The first is display disparity, where connecting heterogeneous tabletop and vertical displays introduces issues in how one seats people around the virtual table and how one orients work artifacts. The second is presence disparity, where a participant’s perception of the presence of others is markedly different depending on whether a collaborator is co-located or remote. This is likely caused by inadequate consequential communication between remote participants, which in turn disrupts group collaborative and communication dynamics. To mitigate display and presence disparity problems, we determine virtual seating positions and replace conventional telepointers with digital arm shadows that extend from a person’s side of the table to their pointer location.
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