Road climbing: Principles governing asymmetric route choices on maps

The focus of this paper was on how people plan routes when using maps. This issue is relevant not only to the design of maps, but also to the construc tion of new navigation systems built to help people plan routes. The resear ch was concerned with the principles that people follow when selecting a ro ute. Specifically, the authors investigated why people's route choices are often asymmetric-why a different route is chosen when traveling between two locations depending on which point is the origin and which is the destinat ion. It is contended that this path asymmetry does not occur randomly; subj ects' route selection is systematic and predictable. Often, subjects will e mploy a heuristic termed here as road climbing, which is similar to hill cl imbing strategies used in problem-solving. Road climbing is a preference fo r long and straight routes in the local area containing the origin. In Expe riment 1, subjects chose paths predicted by a road climbing model even when the selected paths were 50 per cent longer than alternative paths. Moreove r, this effect was exaggerated when subjects processed the maps on a region -by-region basis. In Experiment 2, the results were extended to include rea l maps that subjects may encounter in their day-to-day routines. These resu lts are discussed in terms of their relevance to current problem-solving an d spatial cognition research. Practical applications are also considered. ( C) 1998 Academic Press.