Location and Language Use in Social Media€¦ · · 2015-01-212012-04-04 · Stanford Mobi...
Transcript of Location and Language Use in Social Media€¦ · · 2015-01-212012-04-04 · Stanford Mobi...
Stanford Mobi Social Workshop 2012 | Invited Talk!
Location and Language Use in Social Media!!
Ed H. Chi!!
Google Research!!Work done while at Palo Alto Research Center (Xerox PARC)!
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2012-04-04 Stanford Mobi Social Workshop 2012 Invited Talk 1
What can you do with all this data?
Google Trends Trendalyzer
Big Data Analytics!! Google Analytics Google Website Optimizer
2012-04-04 Stanford Mobi Social Workshop 2012 Invited Talk 2
Model-Driven and Living Laboratory Approach
Characterization
and Modeling
Unlock Understanding
of Collective Intelligence
Intelligent UI
and Data-mining
Applications / Products Living Laboratory
Productization
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Assumptions about the Location Field!
1. Strongly-typed geo information!2. Little noise!3. Good precision!
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27.7 million English Tweets (collected early
2010)
4.6 million Twitter Users
990K+ active Twitter users
10,000 Location Field Entries from Active
Twitter Users
Extracted Their Location Field
Entries
Randomly Sampled
10,000 Entries
Removed Automatically Populated Lat/
Lon Entries (1154)
8846 Manually Entered Twitter Location Field Entries
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31
Two Coders Powered by human knowledge, the Internet, friends + family, etc.
8846 Manually Entered Twitter Location Field Entries
89%+ Agreement
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Some Valid Geographic Information
66%
Nothing Entered
18%
Non-Valid Geographic!Information!
16%!
Study 1: “Geographicness”!
“850 n.benson ave! upland ca”!
“JoviLand, CA”!
“San Francisco”!
“the panhandle”!
“Middle Earth”!
“Global Citizen”!
data quality of the location field!
32!
“New Mexico”!
“Novi Sad, Serbia, Europe”!
“The Moon”!
“Worldwide”!
“kcmo – call the popo”!
2012-04-04 Stanford Mobi Social Workshop 2012 Invited Talk
Information Type # of Users
Popular Culture Reference 195 (12.9%)
Privacy-Oriented 18 (1.2%)
Insulting or Threatening to Reader 69 (4.6%)
Non-Earth Location 75 (5.0%)
Negative Emotion Towards Current Location 48 (3.2%)
Sexual in Nature 49 (3.2%)
Study 1: Non-Geo Information types of non-geographic information entered into the location field
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Information Type # of Users
Popular Culture Reference 195 (12.9%)
Privacy-Oriented 18 (1.2%)
Insulting or Threatening to Reader 69 (4.6%)
Non-Earth Location 75 (5.0%)
Negative Emotion Towards Current Location 48 (3.2%)
Sexual in Nature 49 (3.2%)
types of non-geographic information entered into the location field
Study 1: Non-Geo Information
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“BieberTown”
“My World”
“belieber wonderland”
“JaeJoongs heart”
“Next to Waldo :D”
“somewhere in Glambertville”
“Los Angeles, 2019 (GET IT?)”
“Schrute Farms”
Study 1: Popular Culture References Non-geographic information in the location field in user’s profiles
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Information Type # of Users
Popular Culture Reference 195 (12.9%)
Privacy-Oriented 18 (1.2%)
Insulting or Threatening to Reader 69 (4.6%)
Non-Earth Location 75 (5.0%)
Negative Emotion Towards Current Location 48 (3.2%)
Sexual in Nature 49 (3.2%)
Study 1: Non-Geo Information types of non-geographic information entered into the location field
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“Stalker City”
“Stalking me here isnt enough?”
“MindingMyOwn”
“For me to know n u to find out”
“NONE YA BISNESS”
“UM…STALKER!!”
“kgb answers”
Study 1: Privacy References Non-geographic information in the location field in user’s profiles
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Study 1: Implications
Geocoder
Latitude and Longitude Coordinates
STRONGLY-TYPED GEOGRAPHIC INFORMATION
REQUIRED
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Study 1: Quality Implications
Geocoder
Latitude and Longitude Coordinates
16% Non-Valid Geographic
Information
STRONGLY-TYPED GEOGRAPHIC INFORMATION
REQUIRED
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Study 1: Quality Implications
Yahoo! Geocoder
Non-Valid Geographic Information
16%
“Stalker City”, “NONE YA BISNESS”, “Justin Biebers Heart”, “The Void”, “Redneck Hell”, “In the Middle of Nowhere”, “yer mum”, “BSNBC”, “in God’s Graces’, etc…
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“Loserville :)” (-71.397524, 42.28904)
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“Justin Biebers heart!” (-91.700189, 36.328785)
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Some Valid Geographic Information
!
66%
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27.7 million English Tweets (collected early
2010)
4.6 million Twitter Users
990K+ active Twitter users
10,000 Location Field Entries from Active
Twitter Users
Extracted Their Location Field
Entries
Randomly Sampled
10,000 Entries
Removed Automatically Populated Lat/
Lon Entries (1154)
8846 Manually Entered Twitter Location Field Entries
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33.687456,-84.244945 Seriously?
1154 users?
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Position Information
Self-reported Sensor-based
Global Positioning System (GPS)
WiFi Access Point
Cell Phone Towers
Implicitly Revealed!
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72.10% Accuracy 2.91x better than random
United States? Canada?
United Kingdom? Australia?
Study 2: Country Experiments Uniform Sampling
49
Naïve B
ayes C
lassifier
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United States? Canada?
United Kingdom? Australia?
88.86% Accuracy 1.08x better than random
Study 2: Country Experiments Demographically Proportional Sampling
50
Naïve B
ayes C
lassifier
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Study 2: State Experiments
Naïve B
ayes C
lassifier
30.28% Accuracy
California? Arkansas? New York?
Washington? Texas?
…
5.45x better than random
Uniform Sampling
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Study 2: State Experiments
Naïve B
ayes C
lassifier
27.31% Accuracy
California? Arkansas? New York?
Washington? Texas?
…
1.81x better than random
Demographically Proportional Sampling
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Word Geography Predictiveness calgary Canada 419.42 brisbane Australia 137.29 coolcanuck Canada 78.28 afl Australia 56.24 clegg UK 35.49 cbc Canada 29.40 yelp USA 19.80
Study 2: Predictive Words
Word Geography Predictiveness elk Colorado 90.74 redsox Massachusetts 41.18 biggbi Michigan 24.26 gamecock South Carolina 16.00 crawfish Louisiana 14.87
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1.81x better than random
5.45x better than random
1.08x better than random
2.91x better than random
Tweets Have Implicit Location Information
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This needs to be considered in the
context of implicit location
disclosure!
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Contributions!
1. First characterization study of user location field behavior !
2. Location field behavior is much more complex than has been assumed!
3. The complexity has implication for geography-related HCI technologies!
4. Location field behavior must be considered along with implicit disclosure behavior.!
!
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