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Self-introduction Name: 鲍鲍 (Peng Bao) Research Interests: Popularity Prediction, Information Diffusion, Social Network etc… Grade: In the third year pursuing for the PhD. Group: NASC(Network Analysis and Social Computing) Lab: Research Center of Web Data Science & Engineering Doctoral supervisor: Prof. Xue-Qi Cheng

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Self- introduction. Name: 鲍鹏 (Peng Bao) Research Interests: Popularity Prediction, Information Diffusion, Social Network , etc… Grade: In the third year pursuing for the PhD. Group: NASC(Network Analysis and Social Computing) Lab: Research Center of Web Data Science & Engineering - PowerPoint PPT Presentation

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Self-introduction

Name: 鲍鹏 (Peng Bao)

Research Interests: Popularity Prediction, Information Diffusion, Social Network , etc…

Grade: In the third year pursuing for the PhD.

Group: NASC(Network Analysis and Social Computing)

Lab: Research Center of Web Data Science & Engineering

Doctoral supervisor: Prof. Xue-Qi Cheng

popularity prediction in Microblogging Network

——An empirical study

Authors: Peng Bao, Hua-Wei Shen, Junming Huang, Xue-Qi Cheng

Previous Work

Outline

Background & Motivation Problem definition Related works Preliminary study Structural characteristics Prediction & Results Conclusions and Discussions

Background

BURST of SNS Everyone is a member in

the We the Media age! Sina Weibo plays an more and

more important social role. Opportunities and Challenges

Special issues in Sci./Nat. Computational social science

[D. Lazer et al. Science 323, 721-724 (2009)]

Challenging

An interesting and fundamental question How to track, to understand, and to predict the

information flow on the network? To predict the long-term popularity of online

content is very HARD! Popularity is unequally distributed.

high interaction among users intrinsic interestingness of content external influence from traditional media active period of users

Motivation

Popularity prediction is USEFUL! From technology view

Drive enterprises to design a cost-effective cache and content distribution mechanism system

From business view Help journalists, content providers, advertisers, news

recommend systems to provide information services and to design viral marketing strategy

From sociology view Reveal the human collective behavior Facilitate governors to supervise and to guide public opinion

Increasing availability of data

increase Predictability!

Increasing availability of data

increase Predictability!

Problem definition

Popularity prediction: Given a tweet and its forward information before an indicating time ti, We want to predict the popularity p(tr) at a reference time tr. Indicating time ti : The time at which we observe the

information of a tweet. Reference time tr : The time at which we intend to

predict the popularity of a tweet. Popularity p(t) : The number of times that a tweet is

re-tweeted at time t.

Related works

Temporal correlation based[SzaBo et al. C ACM 2010]

Strong correlation between

Early and later log popularity Linear regression

Visibility and Interestingness based[Lerman et al. WWW 2010]

User behavior modeling Estimate the interestingness

Related works cont.’

Matrix Factorization based[Cui et al. SIGIR 2011]

Estimate the latent factor

of user and item Feature based[Hong et al. WWW 2011]

Formalized to classification problem Logistic regression

Temporal pattern based [Matsubara et al. KDD 2012]

Periodical Avoid infinity Power-law decay

Existing methods mainly focused on the quality of content, the interface of the social media site, the collective behavior of users.

We focus on the structural characteristicsof the networks spanned by early adopters We focus on the structural characteristicsof the networks spanned by early adopters

Preliminary study

Popularity distribution

The popularity of tweets roughly follows a power-law distribution, distributes very unequally. The popularity of tweets roughly follows a power-law distribution, distributes very unequally.

Preliminary study

Lifespan of tweets

Most tweets receive 80% of the final popularity in 24 hours and 90% in 48 hours. The lifespan of tweets follows a log-normal distribution.

Most tweets receive 80% of the final popularity in 24 hours and 90% in 48 hours. The lifespan of tweets follows a log-normal distribution.

Preliminary study

Active period

We should consider the variation in hourly activity cycles The daily variation has no obvious relationship with week cycle and are event-related.

We should consider the variation in hourly activity cycles The daily variation has no obvious relationship with week cycle and are event-related.

“Wenzhou train collision”“Wenzhou train collision”

Temporal correlation of logarithmic popularity

The correlation is weak with large deviation. The Pearson Correlation Coefficients is 0.74 It is less reliable to predict the popularity of a tweet if we just use its earlier popularity alone.

The correlation is weak with large deviation. The Pearson Correlation Coefficients is 0.74 It is less reliable to predict the popularity of a tweet if we just use its earlier popularity alone.

Structural characteristics

We explore the network consisting of early adopters Link density: the ratio of

the number of existing follow-

ship links and the number of

all possible links. Diffusion depth: the length

of the longest path from the

submitter to anyone of them.

Structural characteristics

Empirical found

The structural characteristics provide strong evidence to help estimate the final popularity The structural characteristics provide strong evidence to help estimate the final popularity

Prediction and Results

Comparison approaches: Evaluation methods:

Experiment results

Conclusions

We empirically study structural characteristics, which can provide critical indicators

The prediction accuracy can be significantly improved by incorporating the factor of structural diversity

The conclusion capture the intuition It provides us INSIGHTS to further study

Discussions

Accumulative effect Temporal characteristics Event-based prediction

accumulative Effect of Multiple Exposure in Information

Diffusion on Social Network

On-Going Work

Exposures and Adoptions

Exposures: Node’s neighbor exposes the

node to the contagion Adoption: The node acts (e.g. re-tweet) on

the contagion

t3

t1

t2

Time: t1 < t2 < t3 < … < tn

Problem definition

Exposure Curve: Probability of

re-tweeting a tweet for a user

depends on the number of friends

who have already re-tweeted. Dependence

Example Application

Marketing agency: would like you to adopt/buy product X

They estimate the adoption curve

Should they expose you to X three times? Or, is it better to expose you X, then Y and

then X again?

What we are doing

Classify the TWEETS by Has URL or not Has Event or not Has Multiple Events or not Deeper analysis on the ME for different event

Classify the USERS by User’s degree User’s active period Local clustering coefficient

What we are doing cont.’

Structural diversity between the source of multiple exposures Fix the number of exposure times, check

Link density Number of connected components Temporal effect

Temporal motif

You will see the results soon!You will see the results soon!

Closing Remarks

We should do MORE…

We knew A LITTLE.

We have done MANY!

This field is a piece of WILD but Fertile mineral land.

Acknowledgement

Thank to all members in the NASC group (www.groupnasc.org) for helpful discussions and suggestions

Collaborators

Xue-Qi Cheng, Hua-Wei Shen, Junming Huang

Thanks!

Q$A

Email: [email protected]

Weibo: http://weibo.com/sparkfield