TITLE:

Digital Road Map Accuracy Evaluation: A Buffer-based Approach

PRESENTER:

Shashi Shekhar : Biography , Homepage

AFFILIATION:

Computer Science Department, University of Minnesota.

URL:

http://www.cs.umn.edu/~shekhar

SLIDES:

ABSTRACT:

The quality of digital road maps plays a critical role in many GIS applica- tions. For example, the next generation of automatic road user charge sys- tems will need to be able to identify the road on which a vehicle is traveling and report the total number of miles driven by a vehicle. This requirement imposes a new challenge on the accuracy of digital road maps. Certainly, failure to manage/evaluate errors in digital road maps may limit or invali- date road user charge assessment. Most previous work on the evaluation of the accuracy of digital road maps was focused on point-based approaches and was not scalable to large road networks. In this paper, we present a spatial framework for evaluating digital road map accuracy. First, we ap- plied a buffer-based line-string colocation measure to select a field test site in order to discover high affinity road patterns, i.e., roads located very close together. This served two functions: (1) to determine the magnitude of the problem and (2) to identify the location where map accuracy needs to be evaluated. We then proposed a line-string based digital road map accuracy measure that uses a well-defined buffer computation. Our experiments on a Minneapolis-St. Paul base map demonstrate that our approach is applicable to large road networks and is effective for assessing positional accuracy in digital road maps. Further, we found that the accuracy of existing digital road maps do not satisfy the requirements required for applications such as road user charge systems. The fact is that current digital road maps were not designed for road user charge systems and if used may lead to inaccurate and unfair charges.

KEYWORDS: Spatial Datasets, Accuracy, Digital Roadmaps.

ACKNOWLEDGMENTS: This work was supported in part by the Federal Highway Authority, and the University of Minnesota (e.g. Center for Transportation Studies).

NOTE: Some of the results discussed in this talk appeared in the following publications:

  1. S. Shekhar, X. Ma, H. Xiong, W. Wu, M. Donath, P. Cheng, Digital Road Map Accuracy Evaluation: A Buffer-based Approach, ( pdf ). The joint meeting of The Fifteenth Annual Conference of The International Environmetrics Society and The Sixth International Symposium on Spatial Accuracy Assessment in Natural Resources and Environmental Sciences, 2004.
  2. # P. Cheng, M. Donath, X. Ma, S. Shekhar, and Kenneth Buckeye Evaluation of Digital Maps for Road User Charging Applications User Charge Systems , ( pdf ), In submission to Journal of Transportation Research Board (TRB), 2005.
  3. P. Cheng, X. Ma, M. Donath, and S. Shekhar, Evaluation of National Differential Global Positioning System (ND GPS) for Accessing Road User Charge Systems, ( pdf ), Journal of Transportation Research Board (TRB), 2004.