INTERNATIONAL INSTITUTE FOR GEO-INFORMATION SCIENCE AND EARTH OBSERVATION

Conceptualization of Place via Spatial

Clustering and Co-occurrence Analysis

aInstitute of Information Science, Academia SinicabInternational Institute for Geo–Information Science and Earth Observation (ITC)

Dong–Po Dengab; Tyng–Ruey Chuanga; Rob Lemmensb

2009 International Workshop on Location Based Social Networks (LBSN’09)

Nov. 3, 2009, Seattle, WA, USA

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Introduction

In an insightful exposition of the cultural meaning of place, Yi-Fu Tuan (1975) notes the places may be studied either as a location in a hierarchy of units or as a unique artifact. As an artifact, he regards place as ‘a center of meaning constructed by experience.’ A place may be significant to any individual or group, and may exist at any scale (Tuan 1975: 152). As Tuan notes, the number of such places is hypothetically infinite. However, not all possible places are in fact named and defined as places. Locations become places only when events occur that cause them to become imbued with meaning. Historical gazetteers therefore need to record the occurrences that have made places into centres of meaning

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Photos and Tags in Flickr

Tags

Geo-Tag

Time-Tag

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Where is the beef?

2008 amsterdam canal europe holland netherlands noordholland north travel

Is geospatial data created in a social network a valuable production in and for a geospatial society in general?

How to extract the geospatial information from user-generated contents in a social network?

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Selected photos from Flickr

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Spatial Clustering method (DBSCAN)

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Co-occurrence analysis

Photo-tag matrix

tag-tag correlation matrix

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The correlation between the tag “amsterdam" and the tags of several landmarks associated to Amsterdam

Distance

Correlation coefficient

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Conceptualizing places in different spatial scales

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Conceptualizing places in different spatial scales

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Conceptualizing places in different spatial scales

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Conceptualizing places in different spatial scales

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Conclusions and future works

Without the use of suitable spatial clustering, detailed information about a place is veiled by high frequency tags

A conceptualization of place is unveiled by tag co-occurrences at a suitable spatial scale

Location-based applications can be developed to suggest tags to users as they take photos

In the future we will ground the semantics between pairs of tags via the use of gazetteers or dictionaries

INTERNATIONAL INSTITUTE FOR GEO-INFORMATION SCIENCE AND EARTH OBSERVATION

Thank you for your attention!

deng@itc.nl