VGI contributors’ awareness of geographic information quality and its effect on data quality: a case study from Japan

ABSTRACT

In many countries, geospatial data are typically provided by public institutions. Cities have been mapped using such public data. On the other hand, the demand for geospatial data has been diversifying, given the requirements for mapping cities. To respond to demands for new geospatial data, creation of citizen-generated open data and volunteered geographic information (VGI) have recently become popular. However, the quality of such open data and VGI are not always guaranteed. The number of studies on quality assessments of VGI have increased in recent years. The present study aimed to identify OpenStreetMap (OSM), one type of VGI, as well as contributors’ awareness of data quality, and the relationships between their awareness and the positional accuracy of the OSM data contributed by them. The results showed that awareness or lack of the positional accuracy did not affect the quality of the OSM data created by the contributors. These findings suggest that the crowdsourcing approach might not guarantee the data quality of VGI.

RÉSUMÉ

Dans de nombreux pays, les données géospatiales ont principalement été mises à disposition par des institutions publiques. Les villes ont été cartographiées à partir de ces données publiques. Par ailleurs, la demande en données géospatiales pour cartographier les villes s’est diversifiée. Pour répondre à ces demandes en nouvelles données géospatiales, la création de données ouvertes par les citoyens et l’information géographique participative sont devenues plus actives. Pourtant la qualité de ces données ouvertes et participatives n’est pas toujours garantie. Les études sur la qualité de ces données se sont multipliées ces dernières années. Notre étude a pour but d’étudier les données OpenStreetMap (OSM), données participatives, ainsi que la connaissance qu’ont les contributeurs sur la qualité des données et les relations entre les connaissances qu’ont les contributeurs sur la qualité et la qualité de positionnement des données qu’ils collectent. Les résultats montrent que la connaissance ou l’absence de connaissance des contributeurs sur la précision de localisation n’ont pas d’impact sur la précision de positionnement des données OSM qu’ils saisissent. Ces résultats suggèrent que l’approche participative ne garantit pas la qualité des données participatives.

KEYWORDS:

• OpenStreetMap
• volunteered geographic information
• data quality assessment
• positional accuracy

Acknowledgements

The authors would like to express their gratitude to three reviewers for their valuable comments on early drafts of this article.

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes on contributors

Dr Jun Yamashita is a professor at the Faculty of Social and Cultural Studies, Kyushu University, Japan. His research focuses on volunteered geographic information, participatory GIS, environment-related technologies and urban sustainability transitions.

Dr Toshikazu Seto is a lecturer at the Center for Spatial Information Science, the University of Tokyo, Japan. He is a social geographer and geographical information scientist. In recent years, he has been engaged in research on participatory GIS and civic-tech open data.

Dr Yuichiro Nishimura is an associate professor at Nara Women's University, Japan and specialized in human geography. His research interests cover participatory GIS and mapping, public participation, natural disasters and time geography.

Dr Nobusuke Iwasaki is a principal researcher at Institute for Agro-Environmental Sciences, NARO, and a specialist in geography and rural planning. His research interests address open data, FOSS4G (free and open source software for geospatial), and land use change in rural area.

ORCID

Jun Yamashita http://orcid.org/0000-0001-7435-4918

Toshikazu Seto http://orcid.org/0000-0003-0281-1790

Yuichiro Nishimura http://orcid.org/0000-0002-2685-7841

Nobusuke Iwasaki http://orcid.org/0000-0001-5766-1908

Notes

1. http://www.gsi.go.jp/ENGLISH/page_e30210.html.

2. http://hdyc.neis-one.org/.

3. https://github.com/gsi-cyberjapan/vector-tile-experiment/blob/gh-pages/README_en.md.

4. In the Base Map Information, the whole of Earth is included within a 2⁰ × 2⁰ vector-tile, namely a single square tile, at zoom level 0. At zoom level n, it is covered by 2ⁿ × 2ⁿ vector-tiles.

5. The road centerline data are collected and maintained as per the requirements of the Survey Act (Act No. 188 of 1949). The data are collected using geodetic rather than GPS surveys. For 3 m-wide roads, this act requires the positional accuracy to be less than 0.25 m in the horizontal direction. In the questionnaire survey, OSM users and contributors were queried about their awareness of the data quality, but this study did not examine their knowledge of the positional accuracy or survey method mandated by the Survey Act.

Additional information

Funding

This article was partly supported by the Japan Society for the Promotion of Science (JSPS) KAKENHI [grant number 17K17658].