The Impact on Collaboration of the Inherent Uncertainties of Positioning Technologies

Life on the Edge: Supporting Collaboration in Location-Based Experiences (CHI 2005, April 2005, Portland, USA), by Bendford (Mixed Reality Laboratory, University of Nottingham), Richard Hull (HP Lab in Bistol) and Jo Morrison (NESTA Futurelab) is an ethnological approach to an area I am very interesting in: the user’s experience of positioning technologies (or pervasive technologies in general) and more precisely the impact of their inherent uncertainties. I could find a lot of similarities between their experiment called Savannah and CatchBob! Themes I could bring back to CatchBob! are:

• How does the user interact with invisible sensing systems,
• How (un)awareness are the users of how they are being tracked (e.g. accuracy of the positioning),
• How do users address the difficulty of the system (e.g. when lost of connectivity or no position),
• How do users know and learn how to avoid and rectify the system’s mistakes (e.g. learning to detect the seams and cold spots),
• Do users detect uncertainty and what are the clues,
• How do users establish a shared context and coordinates their actions in moments of uncertainty.

In CatchBob! we thought of giving only rough positioning information or even inaccurate positions. My feeling is that in our game, users are more disturbed by the latency created by the communication system (some players even question if all the messages are being broadcasted) rather by the drift, jitter, lag and unavailability of the positioning system.

Some other pieces of information from this papers and about Savannah:

• Players halt when they encounter new information
• Players assume the the PDA is the sensing object, when in fact the sensor (GPS unit) is on their back
• System latency was also a factor in players’ difficulties; there could be a few seconds delay between a player’s PDA sending a position update, receiving new information from the game server and the player reacting and coming to a halt.
• There appears to be a considerable divergence between the player’s view off forming a group and the underlying system’s view, and this demonstrably can lead to serious confusion and frustration when players are unable to establish a shared context and act together.
• The system view of grouping is far more rigid. The system interprets multiple sources of data, which are often clouded by uncertainty and latency, and makes concrete and discrete decisions about when the groups have formed.
• When is it appropriate to work with absolute position and when relative?