ORIENTATION INFORMATION IN DIFFERENT FORMS OF ROUTE INSTRUCTIONS

Providing quality and easy-to-follow route instructions has been an ongoing research interest. This exploratory work attempts to determine types of information in route instructions that support orientation and cognitive mapping during wayfinding. This study examined a set of 20 verbal route instructions and 18 sketch maps collected from participants. Verbal instructions are first compared with machine generated instructions. Verbal route instructions are then examined based on the adaption of methodology used in generating skeletal descriptions and our addition of categories that emphasize orientation using landmarks. We also consider global landmarks included in both verbal instructions and sketch maps that are off route but supportive for orientation. Results show that human verbal instructions include landmarks and use them intensively for direction and orientation. Results also show that human instructions include both local and global landmarks while sketch maps use more global landmarks for orientation. Landmark types are further analyzed, which shows that in addition to the instructions of turning direction at decision points, participants use landmarks along the route to maintain orientation or direct non-turning movement. AGILE 2013 – Leuven, May 14-17, 2013 2.2 Roles of landmarks Landmarks serve as indicators to identify locations [14, 15] and to gain orientation. Michon and Denis [8] suggested that participants refer to landmarks for reorientation when there is a change of direction or at so-called ‘critical nodes’. The absence of landmarks makes it difficult to follow a route where reorientation is needed or where several choices of directions are possible. Change of orientation is needed at decision points and can be supported by landmarks [7]. The major role of landmarks not at decision points is to confirm or maintain the orientation along a route. Landmarks off route (global landmarks) support novices for overall guidance by providing global orientation [16]. Consequently, research focused only on local landmarks for providing effective route instructions [17]. In the current study, we investigate also the role of landmarks in distance for providing global orientation. 2.3 Skeletal descriptions Denis [18] developed a method called “skeletal descriptions” to shorten wayfinding instructions to a minimum description governing cognitive aspects and remaining fully informative. Instructions given in natural languages were deconstructed into a set of mega-descriptions. The mega-descriptions were then extracted to produce a minimum set of instructions containing only landmarks and actions. In his skeletal descriptions, most landmarks were mentioned at decision points while few were mentioned along route segments as skeletal descriptions omit landmarks along the straight paths and descriptions of landmarks. This view has also been challenged by Lovelace and colleagues [7] that not only landmarks at decisions points are sufficient to construct quality route directions. We also argue that landmarks along straight paths are also important particularly to maintain orientation. Our goal is not to provide minimum set of route instructions but information that is essential for orientation. Therefore, we only adapted Denis’ framework that he used in the first phase to deconstruct route instructions into mega-descriptions for us to further construct categories that address orientation information. To sum up, landmarks play a central role in human wayfinding. Research differentiate roles of landmarks based on their locations: at decision points, between decision points, and off route [7]. While most research so far concentrated on point-like landmarks, we categorized landmarks into local and global ones. Local landmarks are either at decision points or between decision points. Global landmarks are off routes that are not only point-like but also regional. Regional landmarks (e.g. city center) do not exist in maps for navigation and orientation, but they are well-known in everyday communication and are commonly used as landmarks in navigation.