On the relationship between presence and usability in virtual environments: A situated, action based approach

In assessing the usability of a virtual environment, a valuable hint may be offered by a good model of the user's experience, which is usually described as the experience of being 'present' in the environment created by the virtual technology. However, this convergence of usability and presence risks to be undermined by a rather restricted definition of the concept and the habit of evaluating only a limited portion of the environment in which the user is actually present. From this point of view, the major problems reside in the divide between the symbolic and the physical realm, on the one side, and between the simulation and the real world, on the other. In this chapter, we argue that a situated, action-based approach to virtual environments may avoid these drawbacks: users' presence is taken to emerge from the actions performed and usability is referred to the complex object created by the situated interaction with the simulation. After discussing these points, the final section will describe some aspects of an evaluation recently carried out by the authors, where this framework has been applied.