Pointing to a place across a barrier : study of barriers effect on human survey knowledge

Dissertation submitted in partial fulfilment of the requirements for the degree of Master of Science in Geospatial TechnologiesPeople use their mental representation of space to perform activities that involve spatial tasks. Over the past decades, several methods were applied to study the effect of different factors on the way people acquire spatial knowledge. Through a pointing task, this study attempts to investigate the influence of spatial barriers on human survey knowledge in an outdoor environment. The task involved pointing from the same origin to targets in two separate conditions: one target lies across a barrier and another with no barrier in the pointing direction. The experiment was conducted in three locations: two in Muenster city and one in Dortmund city. A total of 204 random subjects participated in the whole experiments. In each location, the number of subjects participating was divided into two equal groups, each group pointing in only one separate condition. Subjects were asked to give an estimation of the direction to the target using a 360° dial, followed by a question about the direction they would go to get to that target. Pointing errors away from the target were calculated and analysed. Preliminary results of the study highlighted interesting patterns in the distribution of pointing error in each condition. One major finding of the study reveals that participants made a higher error in case of pointing across a barrier. In two of the study locations, the results show that in such a case, the pointing error is more biased in accordance with people’s path preference when crossing a barrier to reach a destination, while this effect was not observed in the third location. The study suggests a new viewpoint of understanding how barriers can have an impact on survey knowledge acquisition, and therefore, opens the door to more comprehensive research on this effect. The results also imply that in some cases, such an effect might need to be considered in the process of developing orientation-based applications