THE SKELETON IN THE COGNITIVE MAP A Computational and Empirical Exploration

Experts seem to find routes in complex environments by finding a connection from the source to a “skeleton” of major paths, then moving within the skeleton to the neighborhood of the destination, making a final connection to the destination. The authors present a computational hypothesis that describes the skeleton as emerging from the interaction of three factors: (a) The topological map is represented as a bipartite graph of places and paths, where a path is a one-dimensional ordered set of places; (b) a traveler incrementally accumulates topological relationships, including the relation of a place to a path serving as a dividing boundary separating two regions; and (c) the wayfinding algorithm prefers paths rich in boundary relations so they are likely to acquire more boundary relations. This positive-feedback loop leads to an oligarchy of paths rich in boundary relations. The authors present 81 ENVIRONMENT AND BEHAVIOR, Vol. 35 No. 1, January 2003 81-106 DOI: 10.1177/0013916502238866 © 2003 Sage Publications © 2003 SAGE Publications. All rights reserved. Not for commercial use or unauthorized distribution. at PENNSYLVANIA STATE UNIV on February 6, 2008 http://eab.sagepub.com Downloaded from preliminary computational and empirical tests for this hypothesis, and provide initial results. A THEORY TO EXPLAIN THE SKELETON Expert wayfinders in a complex large-scale environment use a “skeleton” of important paths and places to guide their problem solving (Chase, 1982; Lynch, 1960; Pailhous as cited in Chase, 1982). How is this skeleton represented? How is it acquired? And how does it help in wayfinding? In this article, we describe a preliminary computational hypothesis to explain the phenomenon of the skeleton based on the concepts in the Spatial Semantic Hierarchy (Kuipers, 2000) (which extends the TOUR model; Kuipers, 1978, 1982). We also describe a set of computational and empirical tests that can be applied to this hypothesis. Our preliminary results suggest directions for further investigation.