Generating and evaluating landmark-based navigation instructions in virtual environments

Abstract

Referring to landmarks has been identified to lead to improved navigation instructions. However, a previous corpus study suggests that human “wizards” also choose to refer to street names and generate user-centric instructions. In this paper, we conduct a task-based evaluation of two systems reflecting the wizards’ behaviours and compare them against an improved version of previous landmark-based systems, which resorts to user-centric descriptions if the landmark is estimated to be invisible. We use the GRUVE virtual interactive environment for evaluation. We find that the improved system, which takes visibility into account, outperforms the corpus-based wizard strategies, however not significantly. We also show a significant effect of prior user knowledge, which suggests the usefulness of a user modelling approach.