Mapping Social Networks Using
Head/tail Breaks
Bin Jiang and Ding Ma
University of Gävle, Sweden
http://fromto.hig.se/~bjg/
Big data from location based social
media
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It is NOT just a new type, but...
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A new paradigm geometrically and
statistically
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From a hairball to a clear pattern
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Check-ins data
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Brightkite and Gowalla check-ins
(US mainland as the study area)
Brightkite: April 2008 to October
2010, 2,780,042 locations from
30,927 users
Gowalla: February 2009 to October
2010, 3,303,981 locations from
52,249 users
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The notion of natural cities
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Natural cities refer to objectively or naturally
defined and delineated human settlements, or
human activities in general on Earth’s surface,
using massive geographic information of various
kinds, and based on the head/tail breaks.
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Head/tail breaks
Recursive function Head/tail Breaks:
Break the input data (around mean) into the
head and the tail;
// the head for data values above the mean
// the tail for data values below the mean
while (head <= 40%):
Head/tail Breaks(head);
End function
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Evolution of natural cities
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Mapping social networks (motivation)
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How to map social networks?
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People-people network
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Mapping social networks into
geography
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Location-location network
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City-city network
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Some statistics
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Conclusion
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Social connections greatly reflect human
spatial distribution, and vice verse.
Big data help better understanding both
social and geographic aspects of human
activities including travels.
Head/tail breaks can be effective for both
analyzing and visualizing the big data.
Head/tail breaks thinking is promising for
big data analytics.
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Thank you very much!
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