surveying geonames gazetteer data for the nordic countries
TRANSCRIPT
![Page 1: Surveying GeoNames Gazetteer Data for the Nordic Countries](https://reader034.vdocuments.net/reader034/viewer/2022042906/58a512041a28ab8e1c8b5f65/html5/thumbnails/1.jpg)
Surveying GeoNames
Gazetteer Data for the Nordic Countries
Dirk Ahlers
![Page 2: Surveying GeoNames Gazetteer Data for the Nordic Countries](https://reader034.vdocuments.net/reader034/viewer/2022042906/58a512041a28ab8e1c8b5f65/html5/thumbnails/2.jpg)
2
Motivation Location information is vital for many
applications Gazetteers provide basic geospatial
knowledge Quality is often only implicitly assumed Quality indicators are needed
NIK 2015
![Page 3: Surveying GeoNames Gazetteer Data for the Nordic Countries](https://reader034.vdocuments.net/reader034/viewer/2022042906/58a512041a28ab8e1c8b5f65/html5/thumbnails/3.jpg)
3
Gazetteers Geographical Thesaurus
Coordinates, name, type, hierarchy, population, … Main data source for geoparsing and subsequent
geocoding, ‘what is around’ location finding etc. Data sources
GeoNames.org Large worldwide coverage, freely available
TGN – The Getty Thesaurus of Geographic Names Used in museums, license needed. New: LOD
NIK 2015
![Page 4: Surveying GeoNames Gazetteer Data for the Nordic Countries](https://reader034.vdocuments.net/reader034/viewer/2022042906/58a512041a28ab8e1c8b5f65/html5/thumbnails/4.jpg)
4
Nordic Countries Denmark (DK)
Faroe Islands (FO) and Greenland (GL)
Finland (FI) Åland Islands (AX)
Iceland (IS) Sweden (SE) Norway (NO)
Svalbard and Jan Mayen (SJ) [plus Antarctic territories]
NIK 2015
![Page 5: Surveying GeoNames Gazetteer Data for the Nordic Countries](https://reader034.vdocuments.net/reader034/viewer/2022042906/58a512041a28ab8e1c8b5f65/html5/thumbnails/5.jpg)
5
Comparison GeoNames-TGN
NIK 2015
![Page 6: Surveying GeoNames Gazetteer Data for the Nordic Countries](https://reader034.vdocuments.net/reader034/viewer/2022042906/58a512041a28ab8e1c8b5f65/html5/thumbnails/6.jpg)
6
Mapping all places
NIK 2015
![Page 7: Surveying GeoNames Gazetteer Data for the Nordic Countries](https://reader034.vdocuments.net/reader034/viewer/2022042906/58a512041a28ab8e1c8b5f65/html5/thumbnails/7.jpg)
7
Populated places
NIK 2015
![Page 8: Surveying GeoNames Gazetteer Data for the Nordic Countries](https://reader034.vdocuments.net/reader034/viewer/2022042906/58a512041a28ab8e1c8b5f65/html5/thumbnails/8.jpg)
8
Anomalies Geospatial irregularities
Both large-scale and small-scale Also in metadata
Simplified locations Grid-aligned positions Coverage with “holes” Repeated positions Inaccurate feature classes Places outside their assigned country Near-identical places
NIK 2015
![Page 9: Surveying GeoNames Gazetteer Data for the Nordic Countries](https://reader034.vdocuments.net/reader034/viewer/2022042906/58a512041a28ab8e1c8b5f65/html5/thumbnails/9.jpg)
9
Example: ‘Simplified’ Locations
NIK 2015
![Page 10: Surveying GeoNames Gazetteer Data for the Nordic Countries](https://reader034.vdocuments.net/reader034/viewer/2022042906/58a512041a28ab8e1c8b5f65/html5/thumbnails/10.jpg)
10
Grid positions: Lofoten
NIK 2015
![Page 11: Surveying GeoNames Gazetteer Data for the Nordic Countries](https://reader034.vdocuments.net/reader034/viewer/2022042906/58a512041a28ab8e1c8b5f65/html5/thumbnails/11.jpg)
11
Example: Nordfjord
NIK 2015
![Page 12: Surveying GeoNames Gazetteer Data for the Nordic Countries](https://reader034.vdocuments.net/reader034/viewer/2022042906/58a512041a28ab8e1c8b5f65/html5/thumbnails/12.jpg)
12
Magnitude of error
Dependent on latitude
Distortion or error may influence calculations
Manually edited points may have better positional accuracy
Solution: error annotation?
NIK 2015[Assessment of the Accuracy of GeoNames Gazetteer
Data, GIR2013]
![Page 13: Surveying GeoNames Gazetteer Data for the Nordic Countries](https://reader034.vdocuments.net/reader034/viewer/2022042906/58a512041a28ab8e1c8b5f65/html5/thumbnails/13.jpg)
13
Separating on/off grid
NIK 2015
![Page 14: Surveying GeoNames Gazetteer Data for the Nordic Countries](https://reader034.vdocuments.net/reader034/viewer/2022042906/58a512041a28ab8e1c8b5f65/html5/thumbnails/14.jpg)
14NIK 2015
![Page 15: Surveying GeoNames Gazetteer Data for the Nordic Countries](https://reader034.vdocuments.net/reader034/viewer/2022042906/58a512041a28ab8e1c8b5f65/html5/thumbnails/15.jpg)
15
Intrinsic Quality Indicators
NIK 2015
![Page 16: Surveying GeoNames Gazetteer Data for the Nordic Countries](https://reader034.vdocuments.net/reader034/viewer/2022042906/58a512041a28ab8e1c8b5f65/html5/thumbnails/16.jpg)
16
POIs
NIK 2015
![Page 17: Surveying GeoNames Gazetteer Data for the Nordic Countries](https://reader034.vdocuments.net/reader034/viewer/2022042906/58a512041a28ab8e1c8b5f65/html5/thumbnails/17.jpg)
17
Population numbers
NIK 2015
![Page 18: Surveying GeoNames Gazetteer Data for the Nordic Countries](https://reader034.vdocuments.net/reader034/viewer/2022042906/58a512041a28ab8e1c8b5f65/html5/thumbnails/18.jpg)
18
Conclusion Set of intrinsic indicators
Highlighting of problematic areas Selection according to
requirements Impact depends on granularity
requirements of application Varying quality levels Dependencies differ from
mainland Future work
Provenance data not available, comparison with Web sources
World scale
NIK 2015