Abstract. For many years, theories of collaborative learning
tended to focus on how individuals function in a group. More
recently, the focus has shifted so that the group itself has become
the unit of analysis. In terms of empirical research, the initial goal
was to establish whether and under what circumstances
collaborative learning was more effective than learning alone.
Researchers controlled several independent variables (size of the
group, composition of the group, nature of the task,
communication media, and so on). However, these variables
interacted with one another in a way that made it almost
impossible to establish causal links between the conditions and the
effects of collaboration. Hence, empirical studies have more
recently started to focus less on establishing parameters for
effective collaboration and more on trying to understand the role
which such variables play in mediating interaction. In this chapter,
we argue that this shift to a more process-oriented account
requires new tools for analysing and modelling interactions.