The Geography and Importance of Localness in Geotagged Social Media

By Isaac L. Johnson, Subhasree Sengupta, Johannes Schöning, Brent J. Hecht. 2016

65 citations recorded by the source corpus.

Geotagged tweets and other forms of social media volunteered geographic information (VGI) are becoming increasingly critical to many applications and scientific studies. An important assumption underlying much of this research is that social media VGI is "local", or that its geotags correspond closely with the general home locations of its contributors. We demonstrate through a study on three separate social media communities (Twitter, Flickr, Swarm) that this localness assumption holds in only about 75% of cases. In addition, we show that the geographic contours of localness follow important sociodemographic trends, with social media in, for instance, rural areas and older areas, being substantially less local in character (when controlling for other demographics). We demonstrate through a case study that failure to account for non-local social media VGI can lead to misrepresentative results in social media VGI-based studies. Finally, we compare the methods for determining localness, finding substantial disagreement in certain cases, and highlight new best practices for social media VGI-based studies and systems.

Subfields: Epidemiology, Geography, Planning and Development, Transportation

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Epidemiology

1. Isaac L. Johnson
2. Johannes Schöning
3. Jason I. Hong
4. Brent J. Hecht

In Geography, Planning and Development

1. Isaac L. Johnson
2. Johannes Schöning
3. Brent J. Hecht
4. Connor McMahon

In Transportation

1. Isaac L. Johnson
2. Johannes Schöning
3. Brent J. Hecht
4. Connor McMahon
5. Jason I. Hong

Citations in the corpus

• State of the Geotags: Motivations and Recent Changes (2017, background): “Johnson et al (Johnson et al. 2016) found similar findings: that in Twitter, Flickr, and Swarm, only about 75% of posts are from “local” users, but ours are more extreme; depending on how one defines “local,” anywhere between 11.9% to 46.7% of geotags are from “local” users.”
• The Effect of Population and "Structural" Biases on Social Media-based Algorithms: A Case Study in Geolocation Inference Across the Urban-Rural Spectrum (2017, methodology): “There are two methods used in the literature for determining a user’s home location for use as ground truth in these algorithms (see Johnson et al. [31] for a complete overview of ground truth identification techniques).”