Is it possible to predict elections using social networks? What does the network structure of society tell us about how to predict election results?

1. Voting algorithm in the play Julius
Caesar by William Shakespeare
ZVI LOTKER

2. Elections from wiki
Def: An electionsis a formal decision-making
process by which a population chooses an
individual to hold public office.

3. Voting
Def: Voting is a method for a group, such as
a meeting or an electorate, to make a
decision or express an opinion- often
following discussions, debates,
or electionscampaigns. Democracies elect
holders of high office by voting.

4. But electionsare more than just voting!

5. How can we predict elections?
1. Polling
2. Prediction market
3. Online tools: Google, Facebook, Twitter, etc…

6. What's wrong with polling?
By CLIFF ZUKINJUNE 20, 2015
•2014 midterm elections strong majorities
of the Republican
•Israel’s badly underestimated
prime Minister Benjamin Netanyahu
•In the UK a close elections was predicted
only to see the Conservatives win easily.
Congress: Kevin McCarthy
PM Benjamin Netanyahu
Senate: Mitch McConnell
PM David Cameron

7. Problems of validating algorithms in social networks
1. Privacy -> Anonymity
2. Avoiding open conflict
3. People’s opinions are fluid

8. How to overcome these problems?
1. Build a machine to prove it!
◦ Galileo Galilee
◦ The Large Hadron Collider
◦ Electroencephalography
2. Use the collective memory
◦ Sigmund Freud

9. Julius Caesar for dummies

10. From a play to a graph, Act 4, scene 2
ANTONY: These many, then, shall die; their names are prick'd.
OCTAVIUS: Your brother too must die; consent you, Lepidus?
LEPIDUS: I do consent--
OCTAVIUS: Prick him down, Antony.
LEPIDUS: Upon condition Publius shall not live, Who is your sister's
son, Mark Antony.
ANTONY: He shall not live; look, with a spot I damn him. But, Lepidus,
go you to Caesar's house; Fetch the will hither, and we shall determine
How to cut off some charge in legacies.
ANTONY
OCTAVIUS
LEPIDUS
OCTAVIUS
LEPIDUS
ANTONY
LEPIDUS
OCTAVIUS
ANTONY
OCTAVIUS
ANTONY
OCTAVIUS
ANTONY
OCTAVIUS

11. From a play to a graph, Act 4, scene 2
ANTONY
OCTAVIUS
LEPIDUS
OCTAVIUS
LEPIDUS
ANTONY
LEPIDUS
OCTAVIUS
ANTONY
OCTAVIUS
ANTONY
OCTAVIUS
ANTONY
OCTAVIUS

12. Julius Caesar (play)
Conspirators against Caesar:
1. Marcus Brutus (Brutus)
2. Cassius
3. Casca
4. Decius Brutus
5. Cinna
6. Metellus Cimber
7. Trebonius
8. Caius Ligarius
1. Volumnius
2. Titinius
3. Young Cato
4. Messala
5. Varrus
6. Clitus
7. Claudio
8. Dardanius
9. Strato
10. Lucilius
11. Labeo
12. Flavius
13. Statilius
14. Pindarus
Loyal to Triumvirs after Caesar's death:
1. Octavius Caesar
2. Mark Antony
3. Lepidus
4. Messenger
5. First Soldier
6. Second Soldier
Loyal to Brutus and Cassius:

13. Julius Caesar by William Shakespeare, Act 1
“Beware the ides of March…”
“Let me have men about me that are fat;
[…] Yond Cassius has a lean and hungry
look; He thinks too much: such men are
dangerous.”

14. Julius Caesar by William Shakespeare Act 2
“Cowards die many times before their
deaths; The valiant never taste of death but
once. Of all the wonders that I yet have
heard, It seems to me most strange that men
should fear; Seeing that death, a necessary
end, Will come when it will come.”

15. Julius Caesar by William Shakespeare Act 3
"Friends, Romans, countrymen, lend me your ears; I come to bury Caesar, not to praise him."
“Et tu, Brute?”
[Then fall, Caesar!]

16. Julius Caesar by William Shakespeare Act 4

17. Julius Caesar by William Shakespeare Act 5
“This was the noblest Roman of them all”

18. “Big Brother is Watching You”
"Tell me who your friends are, and I
will tell you who you are"
Or
"Tell me who your friends vote for, and I will
tell you to who you’ll vote for"
The social network
of Brutus
The social network
of Casca

19. “Big Brother is Watching You”
"Tell me who your friends are, and I
will tell you who you are"
Or
"Tell me who your friends vote for, and I
will tell you to who you’ll vote for"
The social network
of Octavius
The social network
of Antony

20. Collapse operation
Collapsed a collection of vertices v1,v2,…vk in to
a single vertex

21. Collapse operation
Collapsed a collection of vertices Cassius and Brutus in to a single vertex

22. Absorbing operation
removing all outgoing edges

23. Absorbing operation
removing all outgoing edges

24. Random walks
Random step:
◦ Move to an adjacent node chosen at random (and
uniformly)
Random walk:
◦ Take an infinite sequence of random steps
Why random
walks are
good?

25. Many Applications
1. Google PageRank
2. Graph exploration
3. Exhibits locality, simplicity, low-overhead, robustness

26. The voting algorithm
1. Collapse the ANCHORS R to a single node and
Collapsed the ANCHORS B to a single node.
2. Make both Node R and B Absorbing.
3. Compute the hitting probability to hit R.

27. How do we find the anchors?
1. In the case of Julius Caesar by
William Shakespeare we look on
the four act.
2. In the general case and more
complicated

28. How do we compute the hitting time?
1. Node v which belongs to the red anchors set,
◦ 𝑅 𝑣 = 1
2. Node v which belongs to the Blue anchors set,
◦ 𝑅 𝑣 = 0
3. The equation of the unknown states
◦ 𝑅 𝑣 =
1
|𝑁 𝑛}
𝑢∈𝑁 𝑛
𝑅 𝑢

29. The results of the voting algorithm in Julisus Caesar
The Complete Play

30. The results of the voting algorithm in Julisus Caesar
The 5 act

31. Compare to community Modularity
{{Antony, Messenger, Lucilius, First Soldier, Second Soldier},
{Brutus, Young Cato, Clitus, Dardanius, Volumnius},
{Cassius, Messala, Tintinius, Pindarus},
{Octavius, Strato}}
Octavius, Antony, Messenger, Lucilius,
First Soldier, Second Soldier
Brutus, Cassius, Messala, Tintinius, Pindarus,
Young Cato, Clitus, Dardanius, Volumnius
, Strato

32. Compare to community Centrality
{{Octavius, Antony, Messenger, Brutus, Cassius, Lucilius,
Messala, Tintinius, Pindarus, Young Cato, Volumnius,
Strato},
{First Soldier, Second Soldier},
{Clitus, Dardanius}}
Octavius, Antony, Messenger, Lucilius,
First Soldier, Second Soldier
Brutus, Cassius, Messala, Tintinius, Pindarus,
Young Cato, Clitus, Dardanius, Volumnius
, Strato

33. Compare to community CliquePercolation
{{Octavius, Antony, Brutus, Cassius, Lucilius, Messala,
Tintinius, Pindarus, First Soldier, Strato},
{Brutus, Clitus, Dardanius, Volumnius},
{Messenger}, {Young Cato}, {Second Soldier}}
Octavius, Antony, Messenger, Lucilius,
First Soldier, Second Soldier
Brutus, Cassius, Messala, Tintinius, Pindarus,
Young Cato, Clitus, Dardanius, Volumnius
, Strato

34. Compare to community Hierarchical
{{Antony, Messenger, Lucilius, First Soldier, Second Soldier},
{Octavius, Brutus, Young Cato, Strato},
{Cassius, Messala, Tintinius, Pindarus},
{Clitus, Dardanius, Volumnius}}
Octavius, Antony, Messenger, Lucilius,
First Soldier, Second Soldier
Brutus, Cassius, Messala, Tintinius, Pindarus,
Young Cato, Clitus, Dardanius, Volumnius
, Strato

35. Compare to community Spectral
{{Antony, Messenger, Lucilius, First Soldier, Second Soldier},
{Octavius, Brutus, Young Cato, Strato},
{Cassius, Messala, Tintinius, Pindarus},
{Clitus, Dardanius, Volumnius}}
Octavius, Antony, Messenger, Lucilius,
First Soldier, Second Soldier
Brutus, Cassius, Messala, Tintinius, Pindarus,
Young Cato, Clitus, Dardanius, Volumnius
, Strato

36. Compare to community VertexMoving
{{Antony, Messenger, Lucilius, First Soldier, Second Soldier},
{Brutus, Young Cato, Clitus, Dardanius, Volumnius},
{Cassius, Messala, Tintinius, Pindarus},
{Octavius, Strato}}
Octavius, Antony, Messenger, Lucilius,
First Soldier, Second Soldier
Brutus, Cassius, Messala, Tintinius, Pindarus,
Young Cato, Clitus, Dardanius, Volumnius
, Strato

37. Compare to community partition
{{Messenger, Brutus, Young Cato, First Soldier, Second Soldier, Clitus,
Dardanius, Volumnius},
{Octavius, Antony, Cassius, Lucilius, Messala, Tintinius,
Pindarus,Strato}}
Octavius, Antony, Messenger, Lucilius,
First Soldier, Second Soldier, Strato
Brutus, Cassius, Messala, Tintinius, Pindarus,
Young Cato, Clitus, Dardanius, Volumnius

38. Thank you!

39. The results of the voting algorithm in the
Karate
{1,2,3,4,5,6,7,8,11,12,13,14,17,18,20,22}
{9,10,15,16,19,21,23,24,25,26,27,28,29,30,31,32,33,34}
1,2,3,4,5,6,7,8,11,12,13,14,17,18,20,22
9,10,15,16,19,21,23,24,25,26,27,28,29,30,31,32,33,34