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Enhancing Public Policy Decision Making using Large-scale

Cell Phone Data

Vanessa Frias-MartinezTelefonica Research

Madrid, Spain

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Cell Phones as Sensors

May 19, 2011, 7:06 pm The Sensors Are Coming!By NICK BILTON

Telecom / WirelessNEWSCellphones for ScienceScientists want to put sensors into everyone's hands

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Cell Phone Data: Calling Records

Calling Records are saved by Telco Companies

Calling Records can be anonymized

Calling Records are saved for all feature and

smartphones (emerging economies)

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Can cell phone data be used to extract specific human

behaviors that might be useful from a policy perspective?

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CDRs

Call Detail Records

BEHAVIORAL VARIABLES

ConsumptionSocial

Mobility

Urban Planning

Tools

Crisis Management

Tools

Global Health Tools

TELEFONICA RESEARCH INSTITUTIONS & POLICY MAKERS

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Cell Phone Data

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Modeling Behaviors

Consumption• Number calls , duration, SMS/MMS/voice• Expenses• Handset Type and Features

Social• Degree of the social network • Weight of the contacts, frequency of communication

Mobility• Diameter of mobility and social network• Radius of gyration• Mobility Patterns

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Computing Cost-Effective Census Maps From Cell Phone Data

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Motivation: Census Maps

A/BC+CDE

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Motivation: Census Maps

A/BC+CDE

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Motivation: Census Maps

A/BC+CDE

Expensive

Specially for Emerging

Economies (every 10 years)

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Cell Phone Data as a proxy of SEL

Consumption

Social

Mobility

SEL PREDICTIVE MODELS

• Higher SELs are correlated to larger areas of mobility• Lower SELs are correlated to smaller social network degrees

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CenCell Tool For Policy Makers

Accuracies up to 80%

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Saving Budget

National Statistical Institutes carry out

surveys

Telcos build models to predict

SELs from Cell Phone Usage

Predict the PresentDetermine SELs for

non-surveyed regions

SAVE BUDGET

National Statistical Institutes carry out

surveys on a subset of regions

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Understanding the Impact of Health Alerts using Cell Phone Data

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H1N1 Mexico Timeline

Preflu

Alert17th April

Closed27th April

Shutdown1st May

Reopen6th May

Measure the impact that government alerts had on the population

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Epidemic Disease Model

Susceptible Exposed Infectious Recovered

Contact Rate

Transition Rate

Recovery Rate

All members within each compartment are assumed to be equal

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Agent-Based Model

Mobility Model

Social Network Model

Disease Model

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Discrete Event Simulator

Mobility ModelSocial Network

Model Disease Model

t₀ t₁ t₂ t₃ … t₉ (1 hour)

M1M2

M3S1

S2S3

D1D2

D3

Using Calling Records from 1st Jan. till 31st.May 2009

Measure the impact that government alerts had on the population’s mobility and on the disease’s spread

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Impact On Population’s Mobility

April 27th May 1st May 6th

Alert Closed Shutdown Reopen

Intervention

Mobility reduced between 10% and 30%

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Impact on Disease Propagation

Baseline (“preflu” behavior all weeks)Intervention (alert,closed,shutdown)

Epidemic peak postponed 40 hours

Reduced number of infected in peak agents by 10%

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CDRs

Call Detail Records

BEHAVIORAL VARIABLES

ConsumptionSocial

Mobility

Urban Planning

Tools

Crisis Management

Tools

Global Health Tools

TELEFONICA RESEARCH INSTITUTIONS & POLICY MAKERS

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Scientific Publications• Vanessa Frias-Martinez, Alberto Rubio and Enrique Frias-Martinez, "Measuring the

Impact of Epidemic Alerts on Human Mobility using Cell-Phone Network Data", Second Workshop on Pervasive Urban Applications @Pervasive 2012, Newcastle, UK

• Vanessa Frias-Martinez, Victor Soto, Jesus Virseda and Enrique Frias-Martinez, "Computing Cost-Effective Census Maps From Cell Phone Traces", Second Workshop on Pervasive Urban Applications @ Pervasive 2012, Newcastle, UK. 

• Vanessa Frias-Martinez and Jesus Virseda and Enrique Frías-Martínez, "SocioEconomic Status and Physical Mobility",Journal of Information Technology for Development (ITD), Special Edition on "ICT and Human Mobility: Cases From Developing Countries and Beyond", February Issue, pages 1-16, 2012

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Scientific Publications• Vanessa Frias-Martinez and Jesus Virseda,"On The Relationship Between Socio-

Economic actors and Cell Phone Usage", 3rd International Conference on Information & Communication Technologies and Development,  ICTD 2012, Atlanta, USA. 

• Enrique Frias-Martinez, Graham Williamson and Vanessa Frias-Martinez, "An Agent-Based Model Of Epidemic Spread Using Human Mobility and Social Network Information", 3rd International Conference on Social Computing (SocialCom'11), Boston, USA, 2011

• Victor Soto and Vanessa Frias-Martinez and Jesus Virseda and Enrique Frias-Martinez, "Prediction of Socioeconomic Levels using Cell Phone Records", International Conference on User Modeling, Adaptation and Personalization (UMAP), Industrial Track, Girona, Spain, 2011.

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Thanks !!

vanessa@tid.eswww.vanessafriasmartinez.org