Alexander Klippel

Structural salience of landmarks for route directions

This paper complements landmark research with an approach to formalize the structural salience of objects along routes. The aim is to automatically integrate salient objects—landmarks—into route directions. To this end, two directions of research are combined: the formalization of salience of objects and the conceptualization of wayfinding actions. We approach structural salience with some taxonomic considerations of point-like objects with respect to their positions along a route and detail the effects of different positions on the conceptualization process. The results are used to extend a formal language of route knowledge, the wayfinding choreme theory. This research contributes to a cognitive foundation for next generation navigation support and to the aim of formalizing geosemantics.

Pictorial representations of routes: chunking route segments during comprehension

Route directions are usually conveyed either by graphical means, i.e. by illustrating the route in a map or drawing a sketch-maps or, linguistically by giving spoken or written route instructions, or by combining both kinds of external representations. In most cases route directions are given in advance, i.e. prior to the actual traveling. But they may also be communicated quasi-simultaneously to the movement along the route, for example, in the case of in-car navigation systems. We dub this latter kind accompanying route directions. Accompanying route direction may be communicated in a dialogue, i.e. with hearer feedback, or, in a monologue, i.e. without hearer feedback. In this article we focus on accompanying route directions without hearer feedback. We start with theoretical considerations from spatial cognition research about the interaction between internal and external representations interconnecting linguistic aspects of verbal route directions with findings from cognitive psychology on route knowledge. In particular we are interested in whether speakers merge elementary route segments into higher order chunks in accompanying route directions. This process, which we identify as spatial chunking, is subsequently investigated in a case study. We have speakers produce accompanying route directions without hearer feedback on the basis of a route that is presented in a spatially veridical map. We vary presentation mode of the route: In the static mode the route in presented as a discrete line, in the dynamic mode, it is presented as a moving dot. Similarities across presentation modes suggest overall organization principles for route directions, which are both independent of the type of route direction-in advance versus accompanying-and of presentation mode-static versus dynamic. We conclude that spatial chunking is a robust and efficient conceptual process that is partly independent of preplanning.

Wayfinding choremes-a language for modeling conceptual route knowledge

The emergent interest in ontological and conceptual approaches to modeling route information results from new information technologies as well as from a multidisciplinary interest in spatial cognition. Linguistics investigates verbal route directions; cartography carries out research on route maps and on the information needs of map users; and computer science develops formal representations of routes with the aim to build new wayfinding applications. In concert with geomatics, ontologies of spatial domain knowledge are assembled while sensing technologies for location-aware wayfinding aids are developed simultaneously (e.g. cell phones, GPS-enabled devices or PDAs). These joint multidisciplinary efforts have enhanced cognitive approaches for route directions. In this article, we propose an interdisciplinary approach to modeling route information, the wayfinding choreme theory. Wayfinding choremes are mental conceptualizations of functional wayfinding and route direction elements. With the wayfinding choreme theory, we propose a formal treatment of (mental) conceptual route knowledge that is based on qualitative calculi and refined by behavioral experimental research. This contribution has three parts: First, we introduce the theory of wayfinding choremes. Second, we present term rewriting rules that are grounded in cognitive principles and can tailor route directions to different user requirements. Third, we exemplify various application scenarios for our approach.

A model for context-specific route directions

Wayfinding, i.e. getting from some origin to a destination, is one of the prime everyday problems humans encounter. It has received a lot of attention in research and many (commercial) systems propose assistance in this task. We present an approach to route directions based on the idea to adapt route directions to route and environments characteristics. The lack of such an adaptation is a major drawback of existing systems. Our approach is based on an information- and representation-theoretic analysis of routes and takes into account findings of behavioral research. The resulting systematics is the framework for the optimization process. We discuss the consequences of using an optimization process for generating route directions and outline its algorithmic realization.

The Cognitive Reality of Schematic Maps

In graphics and language, schematisation is an important method to emphasize certain aspects and to deemphasize others. Different disciplines use schematisation for different reasons. In cartography, graphic schematisation is one aspect of map generalisation. In contrast, cognitive science addresses schematisation as a method to intentionally emphasize certain aspects of knowledge beyond technical necessity; therefore, the notion of schematic map is proposed to denote maps that employ schematisation for cognitive representational reasons. This chapter discusses different views of schematisation from cartography, linguistics, and artificial intelligence. Connections to qualitative reasoning in artificial intelligence are drawn. We address human spatial cognition and present examples of task-oriented representations. Finally, multimodality for conveying spatial knowledge and its application in schematic maps are discussed.

You‐are‐here maps in emergencies –the danger of getting lost

This article evaluates criteria for the design of so‐called You‐Are‐Here (YAH) maps, i.e. maps that explicitly indicate the position of the map reader. Established design criteria are rendered more precise and applied in an exemplary assessment of three YAH maps as they can be found in public buildings as part of a general emergency scheme. The clarification of the YAH map terminology is necessary to allow for assessing the quality of existing YAH maps and consolidates the basis of rule‐based generation of location‐aware information services. Possibilities for further empirical evaluation of YAH maps are discussed and the role of location‐aware technology is considered for smart mobile systems and smart environments.

Linguistic and nonlinguistic turn direction concepts

This paper discusses the conceptualization of turn directions along traveled routes. Foremost, we are interested in the influence that language has on the conceptualization of turn directions. Two experiments are presented that contrast the way people group turns into similarity classes when they expect to verbally label the turns, as compared to when they do not. We are particularly interested in the role that major axes such as the perpendicular left and right axis play--are they boundaries of sectors or central prototypes, or do they have two functions: boundary and prototype? Our results support a) findings that linguistic and nonlinguistic categorization differ and b) that prototypes in linguistic tasks serve additionally as boundaries in nonlinguistic tasks, i.e. they fulfill a double function. We conclude by discussing implications for cognitive models of learning environmental layouts and for route-instruction systems in different modalities.

Landmarks in OpenLS — a data structure for cognitive ergonomic route directions

Landmarks support the structuring of environmental information into cognitive conceptual units, they have the potential to identify uniquely pertinent intersections for route following, and they disambiguate spatial situations at complex intersections. Not using them in automatically generated route directions is a violation of cognitive ergonomics. While we have made great progress on the one hand in characterizing and on the other hand in mining potential landmarks, viable data structures that incorporate their cognitive conceptual functions in route directions are poorly developed. The present article closes this gap by providing a representation based on the OpenLS standard that allows for capturing the semantics of landmarks. In this data structure, the cognitive conceptual essence of a landmark is represented allowing for generating route directions automatically and imbuing street network data with cognitively meaningful elements.

Urban granularities--a data structure for cognitively ergonomic route directions

This paper addresses a data structure specification for route directions that incorporates essential aspects of cognitive information processing. Specifically, we characterize levels of granularity in route directions as the result of the hierarchical organization of urban spatial knowledge. We discuss changes of granularity in route directions that result from combining elementary route information into higher-order elements (so called spatial chunking). We provide a framework that captures the pertinent aspects of spatial chunking. The framework is based on established principles used—from a cognitive perspective—for changing the granularity in route directions. The data structure we specify based on this framework allows us to bridge the gap between results from behavioral cognitive science studies and requirements of information systems. We discuss the theoretical underpinning of the core elements of the data structure and provide examples for its application.

Algorithms for reliable navigation and wayfinding

Wayfinding research has inspired several algorithms that compute the shortest, fastest, or even simplest paths between two locations. Current navigation systems, however, do not take into account the navigational complexity of certain intersections. A short route might involve a number of intersections that are difficult to navigate, because they offer more than one alternative to turn left or right. The navigational complexity of such an intersection may require modified instructions such as veer right. This paper, therefore, presents a reliable path algorithm that minimizes the number of complex intersections with turn ambiguities between two locations along a route. Our algorithm computes the (shortest) most reliable path, i.e., the one with the least turn ambiguities. Furthermore, we develop a variation of this algorithm that balances travel distance and navigational complexity. Simulation results show that traversing a reliable path leads to less navigational errors, which in turn reduces the average travel distance. A further advantage is that reliable paths require simpler instructions.