openstreetmap data quality analysis - eurogeographics · openstreetmap data quality analysis martin...

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OpenStreetMap data quality analysisMartin Raifer, Michael Auer, Lukas Loos, Rafael Troilo, Fabian Kowatsch,

Johannes Visintini & Alexander Zipf

3rd International Workshop on Spatial Data QualityValetta (Malta) · 28.01. - 29.01.2020

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platformOpenStreetMap History Data Analyzing Platform

OSM History

OSM History

Explorer

Flexibility

Flexibility

UsabilityUsability

dashboard

API

OSHDB API

OSHDB

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Agenda

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Prof. Dr. Alexander Zipf

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Focus areas:

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Agenda

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What is OSM?

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What is OSM? A Map

OSM© OpenStreetMap contributors

Bing© OpenStreetMap contributors© HERE

HERE© 2020 HERE, Deutschland

Google Maps© 2020 Geobasis-DE/BKG (© 2009), Google

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What is OSM? Data

OSM Data fetched from Overpass Turbo© OpenStreetMap contributors

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What is OSM? An SDI

PostgreSQLPostGIS

Web APIMap Tiles

DataMetadata

Download serverCurrent OSMFull History

WIKI

Documentation

maps ... editors

5700 million nodes 635 million ways 7 million relations

https://www.openstreetmap.org/stats/data_stats.html

January 2020

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What is OSM? Contributors

https://www.openstreetmap.org/stats/data_stats.html

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What is OSM? Community

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What is OSM? Business

Anderson, J.; Sarkar, D.; Palen, L. Corporate Editors in the Evolving Landscape of OpenStreetMap. ISPRS Int. J. Geo-Inf. 2019, 8, 232

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OSM Data Model

nodes ways relations

tags

k = v

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Agenda

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Considerations

Scepticism

imprecise

laymen’s workvandalism

heterogeneous coverage

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Considerations

TRUST

Thematical

Accuracy

Completeness

Positional

Consistencyi

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Considerations

2 complementing approaches

Extrinsic methods Intrinsic methods

Compare OSM with reference

datasetConsider the history of OSM

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Considerations

TRUST

UsersProcesses

Data development

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Agenda

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Data Extraction: Heidelberg 2008-2018

http://k1z.blog.uni-heidelberg.de/files/2018/12/buildings_addrcity-not-null.gif

buildings

+ address info(addr:city)

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Aggregation: health facilities

http://k1z.blog.uni-heidelberg.de/2019/05/16/exploring-osm-history-the-example-of-health-realted-amenities/

FranceFrance Germany

doctorsclinichospital

amenity

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Strong community impactNepal Earthquake 2015

Auer et al. 2018: Towards Using the Potential of OpenStreetMap History for Disaster Activation Monitoring. Proceedings of the 15th ISCRAM Conference – Rochester, NY, USA May 2018

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Central concepts

● Lossless● Simple, but powerful● High performance● Levels of usability● Flexible deployment: run it local or distributed

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ohsome query

Aggregation

OSM Elements

Users (contributors)

Data extraction

Snapshots

Full History

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ohsomeHeXohsomeHeX

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ohsomeHeX

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ohsomeHeX

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api.ohsome.org

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Recap

OSM has:

… Manpower, transparency of concepts, processes and technology

OSM is:

… Diverse, biased, heterogeneous, rich, poor

BUT: dynamic, thus, able to improve and capable to adapt and innovate

… opens the OSM-History to be included in spatial data quality analyses… can complement extrinsic approaches with novel intrinsic quality indicators… can help you to find out if OSM is fit for your purpose… can give you TRUST

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Questions ?

?

?

?

?

Dr. Michael Auermichael.auer@heigit.org

https://ohsome.org

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Leveraging the Potential of

Open Crowd-Generated Geoinformation and

innovative Geoinformation Technologies

for Citizens and Environment

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Data model

Data partitioning Grid cells with local spatial index OSH Data Entity

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https://downloads.ohsome.org

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OSHDB Java API

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ohsome query - aggregation

Entity Filter

Aggregation

Transformation

Result Filter

Grouping

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ohsome query - aggregation

Entity Filter

Aggregation

Area of Interest

Timerange and resolution

OSM type (node, way, relation)

Thematic selection

Custom filter

Transformation

Result Filter

Grouping By timestamp / boundary / tag / key

Access to all properties (geom, tags, metadata)

Optional, e.g. cleanup

Count, average, sum, count unique, etc.