Diapositiva 0

Robust Land Use Characterization

of Urban Landscapes using Cell Phone Data

June 12, 2011

Vctor Soto & Enrique Fras-Martnez

TELEFNICA I+D

Introduction

01

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Goal: Land use of urban areas using Call Details Records.

Preliminaries

02

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Cell Phone Network

Cell Phone networks are built using Base Transceiver Stations (BTS).

Each BTS will be characterized by a feature vector that describes the calling behavior area.

CDR dataset

Our Dataset

1 month of phone call interactions.

1100 Base Transceiver Stations.

Each CDR contains: phoneSource | phoneDestiny | btsSource | btsDestiny | DD/MM/YYYY | hh:mm:ss | d

Phone number are encrypted to anonymize user identities.

Activity Signature

03

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Representations

Activity signature vectors are built: each component contains the number of managed calls by the BTS in 5-minute intervals.

Land Use Identification

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Methodology (I)

Detect the number of fuzzy clusters c in the signatures dataset using subtractive clustering.

Robust Land Use Analysis

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Why Robust Land Usage?

Land uses in urban landscapes are not well defined

One lot can show several land uses at different degrees.

Often real and planned land uses won't match.

The key:

Fuzzy c-means returns the membership degree of each object to the class representatives. These membership indices can be used to filter robust land uses.

Filtering process

Filtering process

Validation

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Cluster 1: Industrial & Office

Cluster 2: Business & Commercial

Cluster 3: Nightlife

Cluster 4: Leisure & Transport

Cluster 5: Residential

Conclusions & Future Work

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Specific uses for City Halls.

Questions?

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