Position Validation in Crowdsourced Accessibility Mapping
ISBN 978-85-88783-11-9
Authors
1Rice, R.M.; 2Aburizaiza, A.O.; 3Rice, M.T.; 4Qin, H.
1GEORGE MASON UNIVERSITY Email: rrice7@masonlive.gmu.edu
2GEORGE MASON UNIVERSITY Email: aaburiza@masonlive.gmu.edu
3GEORGE MASON UNIVERSITY Email: rice@gmu.edu
4GEORGE MASON UNIVERSITY Email: hqin@masonlive.gmu.edu
Abstract
We live in a society where instant gratification is expected— we demand constantly up-to-date information, which is reflected in our reliance on maps for navigation. Volunteered geographic information (VGI) makes this demand attainable, with popular examples being Waze and OpenStreetMap. At George Mason University (Fairfax, VA), the Office of Disability Services releases an accessibility map once annually, which does not capture the transient obstacles that occur frequently throughout campus, rendering the static map less useful to disabled pedestrians. To fix this dilemma and establish a more useful accessibility system, we have created an application similar to Waze in which contributors report transient obstacles that may impede pedestrian navigation, including sidewalk obstructions, construction detours, and other obstacles that may affect pathway walkability. One of the concerns associated with VGI and geocrowdsourced information is quality assurance, which is imperative when the usage scenarios (including blind, visually-impaired, and mobility-impaired navigation) depend on positional accuracy. This study attempts to address the concerns related to the quality assurance of VGI, specifically quality assessment of the positional accuracy of the geocrowdsourced spatial data. We present our quality assessment techniques and novel methods for assessing the consistency of positional characteristics of geocrowdsourced spatial data related to accessibility. These methods rely on moderated positional assessments, geotags extracted from contributed images, and gazetteer-based geoparsing of location descriptions. Finally, we base our methods and approaches on research contributions and best practices from past and current International Cartographic Association participants in accessibility mapping.