1. AGGREGATING &
ANALYZING THE CONTEXT
OF SOCIAL MEDIA CONTENT
Symeon (Akis) Papadopoulos
Senior Research Scientist @ CERTH
Workshop on Content Verification Tools
June 6, 2018 @ Thessaloniki, Greece

3. Rumours and their spread
Example rumour cascade
Vosoughi, S., Roy, D., & Aral, S. (2018). The spread of true and false news online.
Science, 359(6380), 1146-1151.
Volume of cascades per year
Topic frequency of cascades
Falsehood diffused significantly farther,
faster, deeper, and more broadly than
the truth in all categories of information!

5. Verification of social media content
News organisations / professionals
Verification processes
Social media streams
Verification tools

6. Credibility Signals
Signals Framework, by Aviv Ovadya @ Center for Social Media Responsibility
https://docs.google.com/presentation/d/1pgy43Qbo2yOR13Z7N_1yuuTnR0O4390zSyj2PCHKX4g/

7. Context Analysis & Aggregation Service
Data inference
and aggregation
Input Video
Metadata
from source
User Interface

8. Context Analysis and Aggregation Toolkit
• Back-end service implementation
• Orchestrate data collection from third party services
• Perform data aggregation and indexing
• Perform inferences
• REST API
• http://caa.iti.gr:8080/swagger/?url=http://caa.iti.gr:808
0/Context_Aggregation_and_Analysis_v8.json
• Web-based user interface
• http://caa.iti.gr/
• InVID Plug-in tab
• To be demonstrated in hands-on session

9. Overview of features
• Video metadata from platform of interest
• Video publisher metadata (e.g. YouTube channel,
Twitter account, Facebook page)
• Comments & verification comments
• Instant generation of video thumbnails and
shortcuts for reverse image search
• Weather at the claimed time and place of video
• Twitter sharing timeline
• Includes credibility-oriented classification of tweets
In InVID Plugin

10. Context Analysis in InVID Plugin

11. Web-based User Interface

12. Linked tool: Tweet Verification Assistant
http://tiny.cc/tw_verify

13. The Fake Video Corpus
• 200 fake and 188 real newsworthy videos
• 2206 fake and 1209 real near-duplicates
• YouTube search & visual similarity filtering
• 388 cascades of near-duplicate videos

14. Temporal profiles of video cascades
• Fake videos keep
reappearing years
later
• Real videos tend
to be reproduced
mostly during the
first month

15. Automatic Contextual Verification
• Different classification approaches
• Comment cred: Use Tweet Verification Assistant and aggregate
comment cred scores into a histogram that is used as feature vector
• Video metadata: Train SVM classifier using text-based metadata
from video description and channel statistics
• Fusion: concatenate comment cred and video metadata vectors
• Training on Fake Video Corpus
• Challenge: Generalize on future cases
F1-Score
Comment cred 0.64
Video metadata 0.77
Fusion 0.78
Ideal fusion 0.96
Ideal fusion is a
hypothetical optimal way
to combine comment cred
and video metadata.

16. Summary
• Media-based disinformation is complex!
• Misleading content tends to be shared more!
• There are several technologies available for tackling
the problem, each with its limitations
• End users (journalists) should be the beginning and
the end of the verification process!
• Technology on its own is not sufficient: we need to
take into account the human and social facets of
the problem: media literacy!

17. Thank you for your attention!
https://revealproject.eu/
http://www.invid-project.eu/
Get in touch!
Symeon Papadopoulos papadop@iti.gr / @sympap
Olga Papadopoulou olgapapa@iti.gr / @olgapapa

18. Ex. 1: Unbelievable Explosion Moment In Brussel Airport
https://www.youtube.com/watch?v=mZes8-tzZ0w

19. Ex.2: Video claiming to depict a Hezbollah sniper
https://www.youtube.com/watch?v=nkQ-ij3LTTM

20. Ex. 3: Huge Pod of Mermaids Caught on Tape by DRONE
https://www.youtube.com/watch?v=c7GJPhwSFHQ

21. Ex. 4: Snowboarder Girl Chased By Bear
https://www.youtube.com/watch?v=vT_PNKg3v7s

22. Ex. 5: Syrian hero boy rescue girl in shootout
https://www.youtube.com/watch?v=UTeqpMQKZaY

23. Ex. 6: Unbelievable Explosion Moment In Brussel Airport
https://www.youtube.com/watch?v=mSFf2mzCrTg

24. Ex. 7: Pope Francis SLAPS Donald Trump's Hand….
https://www.youtube.com/watch?v=Q8AQler0Dq0

25. Ex. 8: Lion takes revenge on trophy hunter
https://www.facebook.com/uniladmag/videos/2293398324016547/

26. Ex. 9: Terry Tufferson channel
https://www.youtube.com/channel/UCHH9FQBvo3X4Vmf78c0OASw/videos