Searching for the missing link

Hypertexts may be implicitly structured, based on either node content or context. In this paper, we examine implicit structures that rely on the interpretation of node’s spatial context. Hypertext authors and readers can perceive and understand these idiosyncratic structures, but, because they are implicit, they cannot be used by the system to support users’ activities. We have explored spatially structured hypertext authored in three different systems, and have developed heuristic recognition algorithms based on the results of our analyses of the kinds of structures that people build. Our results indicate that (1) recognition of implicit structures in spatial hypertext is feasible, (2) interaction will be important in guiding such recognition, and (3) the hypertext system can provide layout facilities that will render later systematic interpretation much easier. Found structures can be used as a basis for supporting information management, as a straightforward way of promoting knowledge-base evolution, as a way of solving representational problems endemic to many hypertext systems, or as a basis for collaboration or interaction.