*** Presented by Christopher Barron at State of the Map 2013 *** For the video please see http://lanyrd.com/2013/sotm/scphkr/ *** Full schedule also available at http://wiki.openstreetmap.org/wiki/State_Of_The_Map_2013 For the purpose of data quality evaluation OSM is almost always compared with reference datasets. However, these datasets are not always accessible due to the lack of availability, contradictory licensing restrictions or high procurement costs. An OSM-Full- History Dump can serve as an alternative source for quality evaluations. Using so-called intrinsic indicators the quality of OSM datasets can be assessed with the help of the data's history. We will present why and how the history of OSM objects matter and which tools were used. For this purpose, examples for selected cities around the world are analysed and compared with each other to reveal differences in terms of OSM data quality based on the history of the dataset's objects.

1. Using the History of OSM for
Quality Assessment
Christopher Barron, Pascal Neis, Alexander Zipf
Geoinformatics Research Group,
Institute of Geography
Heidelberg University
Christopher Barron, Geoinformatics Research Group,
Institute of Geography, Heidelberg University

2. How can we evaluate OSM datasets without a
reference dataset?
Christopher Barron, Geoinformatics Research Group,
Institute of Geography, Heidelberg University
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3. Christopher Barron, Geoinformatics Research Group,
Institute of Geography, Heidelberg University
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4. Christopher Barron, Geoinformatics Research Group,
Institute of Geography, Heidelberg University
4

5. Methods for Quality Analysis
based on an OSM-Full-HistoryDump
 Intrinsic Approach
Christopher Barron, Geoinformatics Research Group,
Institute of Geography, Heidelberg University
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6. iOSMAnalyzer - Architecture
Christopher Barron, Geoinformatics Research Group,
Institute of Geography, Heidelberg University
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7. Examples
Christopher Barron, Geoinformatics Research Group,
Institute of Geography, Heidelberg University
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8. Total Road Network Length (1/6)
Mapped completely
Assumption (Neis et al. 2012):
1)
2)
3)
4)
Motorways/Highways
Secondary/Tertiary Roads
Residential Roads
Tracks, Paths, etc.
Christopher Barron, Geoinformatics Research Group,
Institute of Geography, Heidelberg University
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9. Total Road Network Length (1/6)
Madrid
Yaoundé
Christopher Barron, Geoinformatics Research Group,
Institute of Geography, Heidelberg University
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10. Positional Accuracy of Junctions (2/6)
Helbich et al. (2012)
Christopher Barron, Geoinformatics Research Group,
Institute of Geography, Heidelberg University
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11. Positional Accuracy of Junctions (2/6)
Madrid
Christopher Barron, Geoinformatics Research Group,
Institute of Geography, Heidelberg University
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12. Buildings & House Numbers (3/6)
Salzburg
Christopher Barron, Geoinformatics Research Group,
Institute of Geography, Heidelberg University
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13. Buildings & House Numbers (3/6)
San Francisco
Christopher Barron, Geoinformatics Research Group,
Institute of Geography, Heidelberg University
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14. Buildings & House Numbers (3/6)
Yaoundé
Christopher Barron, Geoinformatics Research Group,
Institute of Geography, Heidelberg University
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15. Topological Errors (4/6)
San Francisco
Christopher Barron, Geoinformatics Research Group,
Institute of Geography, Heidelberg University
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16. Currentness of Data (5/6)
Salzburg
Christopher Barron, Geoinformatics Research Group,
Institute of Geography, Heidelberg University
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17. Roads without a name or ref Tag (6/6)
Yaoundé
Christopher Barron, Geoinformatics Research Group,
Institute of Geography, Heidelberg University
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18. Summary
• Q = {V1, V2 … Vn-1}
• OSM quality analyses …
– based on OSM-Full-History-Dumps;
– are possible without reference datasets;
– are arbitrarily repeatable.
Christopher Barron, Geoinformatics Research Group,
Institute of Geography, Heidelberg University
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19. https://github.com/zehpunktbarron/iOSMAnalyzer
GNU GPL Version 3
Christopher Barron, Geoinformatics Research Group,
Institute of Geography, Heidelberg University
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20. Thank you for your attention!
Christopher Barron
Geoinformatics Research Group
Heidelberg University
http://giscience.uni-hd.de
christopher.barron@geog.uni-heidelberg.de
Christopher Barron, Geoinformatics Research Group,
Institute of Geography, Heidelberg University
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