A High-level Cognitive Framework for Route Directions

This paper introduces a framework for route directions based on research results from cognitive science. Contrary to existing route planning systems this approach focuses on cognitive aspects to improve the communication of route knowledge. In order to achieve cognitively adequate communication we need to (a) organise data according to the cognitive model of the wayfinder and (b) specify this organisation in a format that is usable by information systems. These requirements are reflected in the structure of this article. First we provide an overview of results of research on cognitively adequate route directions and detail which aspects of good route directions have already been implemented and where additional work is needed. The question of what makes a route direction cognitively adequate is answered from the perspective of basic research. In this context we discuss approaches to formalise route knowledge: as a kind of spatial ontology, the conceptualisation of directions at decision points, the chunking of route direction elements, the enrichment of route directions with landmarks, the disambiguation of spatial situations and the interplay of language and graphics in multimodal communication systems and their relation to the underlying conceptual structure. A developing standard for location based services is the OpenGIS Location Services (OpenLS) specification. We describe briefly the functionality of the services and their technical basis. The focus is placed on the structure of the navigation service revealing where—from a cognitive perspective—improvements can be made. Based on this analysis we propose to modify the OpenLS standard and to extend its functionality. This modification is exemplarily discussed for direction concepts at different intersections; the final specification is a work in progress. In conclusion we discuss remaining problems and missing research topics necessary to make route directions cognitively adequate.