Wayfinding choremes—a language for modeling conceptual route knowledge

Urban granularities—a data structure for cognitively ergonomic route directions

“…A route is a sequence of such decision point / action pairs. Abstracting from individual decision points leads to higher-order route direction elements, HORDE [28]. We term this abstraction process spatial chunking [27].…”

“…In this section, we connect the UKDS to existing approaches that implement different chunking principles. We will especially focus on the wayfinding choreme theory [28] and context-specific route directions [44], as a possibility to define the best possible level of granularity for a specific route.…”

“…The wayfinding choreme theory addresses the conceptualization and formal modeling of route knowledge [28]. Comparable to the primitive (in the sense of being foundational, not atomic) in the UKDS, i.e.…”

“…To formally handle transitions between different levels of granularity two concepts can be applied. First, the grouping of primitive elements into chunks, or higher order route direction elements (HORDE), is characterized as the wayfinding choreme route grammar (WCRG) [28], which is formally defined as a tuple (N, T, P, S). N is a finite set of nonterminal symbols, T is a finite set of terminal symbols (disjoint from N ), P is a finite set of production rules, and S is the start symbol.…”

“…This issue will dominate the discussions throughout this paper. Generally, the following approaches to route information can be distinguished: a) those that take a complete route as input and optimize route directions for this particular route [9,44,28]; b) those that optimize the route choice based on cognitive aspects, for example, to ease the description of the route or to reduce the likelyhood of getting lost [13,5,20]; c) those that differentiate between parts of the environment that are known to the wayfinder and parts that are unknown. The idea here is to provide only coarse information for the known parts (i.e., to abstract from a concrete route and only announce (intermediate) destinations), while being detailed in the unknown parts (i.e., giving turn-by-turn instructions) there [41,22,47,53,49,46].…”