Volunteered Geographic Information

GIS 314

www.ushahidi.com

Another Example of VGI

• An open source project for crowdsourced information collection, visualisation, and interactive mapping.

• Means “testimony” in Swahili; Created in 2008 to map election violence in Kenya; Further developed after 2010 earthquake in Haiti.

• Typically used for crisis response and human rights advocacy; Also environmental mapping, citizen journalism, and international development.

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www.ushahidi.com

Another Example of VGI

The Process:

• User creates parameters for expected tags/keywords using front-end interface - SMS, RSS, text, email, web.

• User sends a deployment out into the world -

"Text to #1248" "Tweet @haitiquake" "FB #haitiquake" "Email haitiquake@ushahidi.com"

• Tags/keywords become fields for crowdsourced data, populating tables and maps.

Join data from:

Developed by:

Add OSM:

What kind of DDBMS is Ushahidi - Relational or NoSQL?

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In Review

Distributed Database (DDB):

• A logically interrelated collection of shared data distributed over a computer network.

Distributed Database Management System (DDBMS):

• Can be Relational/SQL (Library catalogue, Ushahidi) or NoSQL (CrisisNet, HOT).

• Should look and function exactly like a non-distributed database.

• Real time Social Media data mining and download (the firehose) - Starting point;

requires validation. Not true VGI, maybe "Ambient Geographic Information"

• HOT is the real deal VGI - remote volunteers create OSM polygons and geotags.

Local volunteers contribute point data and other details. All the Geodata is Volunteered.

• Ushahidi pulls it together. It does it all (and it does it well) !

Your Assignment:

• Login to OpenStreetMap or create a new account.
• Follow the HOT tutorial @ www.hotosm.org/get-involved/disaster-mapping
• Go to the HOT Tasking Manager and complete one task square.

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DDBMS 4 VGI @ SGRC :

OMG ! <3

or

WTF ? :-(

Volunteered Geographic Information is: the widespread engagement of large numbers of public citizens in the creation of geographic information; a subset of User Generated Content that contains geographic reference, either explicitly or implicitly.

(Goodchild 2007; Craglia et al. 2012; Elwood et al. 2012)

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crisis.net

www.echosec.net/faq/

Continuous, real-time social media mining + download.

• Search based on filters defined by the user.
• Echosec is a commercial service available by subscription

($$ + no skills).

• CrisisNet is an open source service to create your own API

(skills + no $$).

Requires validation. A starting point for further investigation + "human processing." Why?

Is this "Volunteered" Geographic Information ??

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How is VGI compiled, organized, and managed?

Distributed Databases (DDB):

• A logically interrelated collection of shared data distributed over a computer network.

• Each site is a database in its own right.

• Sites coordinate so user can access data anywhere exactly as if stored locally.

• A "union" of databases.

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Distributed Database Management System

(DDBMS):

• Data is split into fragments across DDB sites; Each site is controlled by the DDBMS.

• Handles local applications independently and participates in at least one global application.

• DDBMS Rules: locally autonomous, continuously operational, non-reliant on any central site.

• To the user a DDB should look and function exactly like a non-distributed database.

4

Volunteered

Geographic

Information

Interrelated does not necessarily mean RELATIONAL

Homogenous DDBMS:

• A homogenous DDBMS utilizes common fields across all sites.

• These are Relational/SQL DDBs.

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Interrelated does not necessarily mean RELATIONAL

Heterogeneous DDBMS:

• A heterogeneous DDBMS translates multiple data models so they can work together.

• This is done when databases are implemented seperately and integrated later.

• These are NoSQL DDBMS

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Volunteered Geographic Information is: the widespread engagement of large numbers of public citizens in the creation of geographic information; a subset of User Generated Content that contains geographic reference, either explicitly or implicitly.

(Goodchild 2007; Craglia et al. 2012; Elwood et al. 2012)

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www.hotosm.org

One Example of VGI

The Process:

• A requesting organization will identify area(s) needing rapid mapping in OSM: Red Cross, MSF, Missing Maps.

• An OSM administrator ensures there is suitable satellite imagery to trace, and creates a project.

• Remote HOT mappers select available task squares and trace polygons, marking squares when complete - Mapathons !

• Other HOT volunteers check quality of mapped squares, marking squares as validated.

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One Example of VGI

The Process, continued:

• Agencies export project basemaps from OSM for use in the field. Data is updated at one minute intervals !

• If available, local volunteers add more detailed features, such as street names or remote villages, using Field Papers ...

• With or without GPS, print task square as basemap, write and draw on it, scan or photograph Field Paper, and upload.

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Karen D. Godbout | April 5, 2017

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