EVENT DETECTION IN TIME SERIES OF MOBILE COMMUNICATION GRAPHS Leman Akoglu Christos Faloutsos.
Carnegie Mellon School of Computer Science Modeling Website Popularity Competition in the...
Transcript of Carnegie Mellon School of Computer Science Modeling Website Popularity Competition in the...
Carnegie MellonSchool of Computer Science
Modeling Website Popularity Competition in the Attention-Activity
Marketplace
Bruno Ribeiro Christos FaloutsosCarnegie Mellon University
WSDM 2015February 5, 2015
Bruno Ribeiro ([email protected])Carnegie MellonSchool of Computer Science
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Motivation
Bought for $580 million
in 2005
Sold for $35 million in
2011
*source: TechCrunch
MySpace’s demise
Sold
Hi5Friendster
Summer 2008
Summer 2008
Bruno Ribeiro ([email protected])Carnegie MellonSchool of Computer Science
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Predicting Network Popularity w/
Competition
Goal:
Why:
??
?
Summer 2008
Fract
ion o
f A
ctiv
e U
sers
(t)
-$545 million dollars
Bruno Ribeiro ([email protected])Carnegie MellonSchool of Computer Science
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new adopters/semester
MySpace.com until late 2008
No Structural Telltale Signs of MySpace’s Demise
Matches known theoretical behaviorMansfield’61, Rogers’03, Bass’69
Total Adopters
0Innovators2.5 %
EarlyAdopters13.5 %
EarlyMajority34 %
LateMajority34 %
Laggards16 %
And no abrupt topological changes in 2008
MySpace graph until recently:• 35 million users
★ http://www.myspace.com
Bruno Ribeiro ([email protected])Carnegie MellonSchool of Computer Science
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Economics:◦ (Mansfield ’63)◦ (Katz&Shapiro’85) ◦ (Farrell&Saloner
’86)◦ (Choi ’94)◦ (Arthur ’94)
Marketing:◦ (Bass ’69)◦ (Fisher&Pry ’71)
Fract
ion o
f A
ctiv
e U
sers
(t)
Summer 2008
Background: Vast Adoption Literature
Computer Science: (Kempe et al ’03) (Zhao et al., IMC’12) (Leskovec et al.,
SIGKDD’08) (Ugander et al., PNAS’12) (Aral&Walker,
Science’12)
Sociology:o (Ryan&Gross’49)o (Everett ’62, ’03)o (Rogers ’03)o (Centola ’12)
Adopt ≠ Active
We know how to model adoption
But how to model attention?
Bruno Ribeiro ([email protected])Carnegie MellonSchool of Computer Science
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1969 - H. A. Simon on information overload:
Information consumes attention (time)
◦ Information-rich world Attention-poor world
Systems that “talk” more than “think” exacerbate
information overload
Attention & Information Overload
Bruno Ribeiro ([email protected])Carnegie MellonSchool of Computer Science
Facebookattention& activity
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How Facebook Talks (a lot)
Bruno Ribeiro ([email protected])Carnegie MellonSchool of Computer Science
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My Attentio
n
My Content
Friends’ Attentio
n
Friends’ Content
Positive & Negative Attention Loops
Positive
Growth
Negative Growth
WebsiteSurvives
WebsiteDies
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Proposed Competition Model
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Proposed State Space
states ∅yUy Ay Iy
∅x
UxAxIx
Both x & y Only y for now Only x for now
Neither for now Not interested in x/y
User Subscribes to:
WebsiteKillers
Never! Unaware Active Inactive
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Model Transitions
User Competition
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Isolated Network Transitions
states ∅yUy Ay Iy SUM
∅x
Ux S(U, )∅ (t)
Ax S(A, )∅ (t) S(A,*)(t)
Ix S(I, )∅ (t)
Media/Marketing gets new subscribers Word of mouth gets subscribers
Network x activity attracts user back
Other activitytakes user away from x
Details
Bruno Ribeiro ([email protected])Carnegie MellonSchool of Computer Science
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Model Predictions with Constant Distraction Factor
Predicting Online Social
Network Popularity
◦ How websites do on
their own
◦ Evolution with
competition
Outline
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Signatures of Self-Sustainability
Long-term User Activity[Ribeiro’14]
Relative attractiveness of activity
Fract
ion
of
Act
ive U
sers
(t)
Fract
ion
of
Act
ive U
sers
(t)
t t
≅1MySpace
Bruno Ribeiro ([email protected])Carnegie MellonSchool of Computer Science
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Signatures of Popularity Growth
Model prediction: Signatures of activity growth[Ribeiro’14]
t tFract
ion
of
Act
ive U
sers
(t)
Fract
ion
of
Act
ive U
sers
(t)
Wor
d of
mou
th
Med
ia &
Mar
ketin
g
Bruno Ribeiro ([email protected])Carnegie MellonSchool of Computer Science
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Predictions with Changing Distractions
t
Predicting Online Social
Network Popularity
◦ How websites do on
their own
◦ Evolution with
competition
Outline
Bruno Ribeiro ([email protected])Carnegie MellonSchool of Computer Science
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Two observable states: S(A,*)(t) and S(*,A)(t)
Remaining states latent & treated as parameters
Data from Alexa.com
Fitted with Levenberg–Marquardt algorithm using squared error
Model Fitting
S(A,*)(t)
S(I,*)(t)?S(U,*)(t)?S(A,I)(t)?S(A,A)(t)?S(A,U)(t)?S(A, )∅ (t)?S(I, )∅ (t)?S(U, )∅ (t)?
friendster.com
Fract
ion
of
Act
ive U
sers
(t)
Details
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MySpace
Friendster
Multiply
Hi5
Facebook Introduces Wall
Distraction of Concurrent UsersIncreases as Facebook Introduces
Wall
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Results (Facebook x MySpace)
t
value
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Results (Facebook x Multiply)
t
value
Multiply
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Results (Facebook x Hi5)
t
value
Hi5
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Results (Facebook x Hi5)
Model Captures Coexistence and Then
Death of Facebook Competitors
Too Many Concurrent Users = Fragility
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Attention feedback helps predict /
understand network survival
No marketing can save from negative
attention loop
Insights from model
◦ E.g.: Metrics of node centrality should take
attention feedback into account
Conclusions
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Thank you!
Questions?
http://www.cs.cmu.edu/~ribeiro@brunofmr