Grounding in Multi-modal Task-Oriented Collaboration

This paper describes the first results of a series of experiments on multi-modal computer-supported collaborative problem solving. Pairs of subjects have to solve a murder story in a MOO environment, using also a shared whiteboard for communication. While collaboration if often described as the process of building a shared conception of the problem, our protocols show that the subjects actually create different shared spaces. These spaces are connected to each other by functional relationship: some information in space X has to be grounded in order to ground information is space Y. The reason to dissociate these spaces is that the grounding mechanisms are different, because the nature of information to be grounded is itself different. The second observation concerns the modality of grounding. We expected that subjects would use drawings to ground verbal utterances. Actually, they use three modes of interaction: (dialogue, drawing, but also action in the MOO environment) in a more symmetrical way. Grounding is often performed across different modes (e.g. an information presented in dialogue is grounded by an action in the MOO).