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Motivation
Related workConcentrates on unstructured knowledge bases
Solution IdeaContext Problems
Corpus Construction
SIGIR '15 - Santiago de Chile [email protected]
Towards Vandalism Detection in Knowledge Bases:Corpus Construction and Analysis
Stefan Heindorf Martin Potthast Benno Stein Gregor Engels
Corpus Analysis
Conclusion & Outlook• Vandalism can reduce the quality of knowledge bases• First standardized corpus to study vandalism in structured knowledge bases• Next step: detect vandalism automatically
Downloadour corpus!
Manual Validation1,000 rollbacked revision
Manually reviewed 1,000 undone/reverted revisions1,000 inconspicuous revisions
Option 1: Rollback (by administrators)86 ± 3 %* revisions indeed vandalism
Option 2: Undo/Restore (by all users)62 ± 3 %* revisions indeed vandalism
* 95 % confidence level
Overview of Corpus• 24 million revisions• 103 thousand vandalism revisions
Corpus Revisions over Time
What is vandalized? Who vandalizes?
For our corpus:Rollbacked revisions are considered vandalism
Information systems structuredknowledge bases
Patrollers are busy
Vandalism is notdetected in time
Some people vandalize those knowledge bases MLMachine learning
to detect vandalismVandalismcorpus
Vandalism?Revision 1: yesRevision 2: no
⋮
use
40% of vandalismin structured data
New features beneficial86 % of vandalism
by unregistered users
57%
3%8%
32%
Top vandalized items Top items by category
Unregistered
Registered
Cases Item title47 Cristiano Ronaldo43 Lionel Messi43 One Direction41 Portal:Featured content34 Justin Bieber33 Barack Obama29 English Wikipedia29 Selena Gomez
Contributions• Wikidata Vandalism Corpus WDVC-2015• Corpus analysis
Automatic Revision Labeling• Wikidata revision history• Only non-bot revisions considered• Goal: Automatic labeling as vandalism/non-vandalism
Option 1: Rollback (by administrators)103,205 rollbacked revisions
Option 2: Undo/Restore (by all users)64,820 undone/reverted revisions
1
2
3
4
2
5
revert
20%
20%
16%
14%
13%
9%
8%
1%
12%
21%
9%
15%
8%
4%
31%
1%
Culture
People
Society
Nature
Meta items
Technology
Places
Other
Top 1,000 vandalized itemsTop 1,000 of all items
http://www.uni-weimar.de/en/media/
chairs/webis/corpora/corpus-wdvc-15/