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An Introduction to Spatial Data: Sources & Methods

An Introduction to Spatial Data: Sources & Methods

This talk aims to be an introduction to Geo, for non Geo types. It was given to DIT MSc (Computer Science) students on Sat 23rd March 2013

Richard Cantwell

March 25, 2013
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  1. An Introduction to Spatial Data: Sources and Methods Richard Cantwell

    Senior GIS Consultant / Technical Manager www.gamma.ie [email protected] @ManAboutCouch
  2. Pre rendered tiles – Range of data sources AJAX (Asynchronous

    JavaScript and XML) Open API's - Mashups Rapid development – releases every 7-10 days Google Earth Google Maps - Key Innovations http://berglondon.com/projects/hat/
  3. “A piece of content or data is Open if you

    are free to use, reuse, and redistribute it - subject only, at most, to the requirement to attribute and share-alike.” www.opendefinition.org http://flic.kr/p/7Aqgs5
  4. Tobler’s First Law of Geography: "Everything is related to everything

    else.. But near things are more related than distant things."
  5. Extract Raw Data – Embedded in a map <div> on

    a web page OpenLayers & OSM Overpass API
  6. VGI: OpenStreetMap • Limited to what is ‘visible’ • API’s

    limited, aimed at data editors • ‘Viral’ nature of data licence • Focus on map data • ‘Warm Geography’ • Aims to be of Public Interest • Instant data updates, Sporadic • ‘Depth’ Issues (coverage, completeness) • Weak Metadata / Standards Commercial GeoData Providers • Wide source of inputs • API’s extensive, aimed at data consumers • Derived data issues • Focus on services • ‘Cold Geography’ • Aims to be Authoritive • Moderated update process, Consistent • ‘Width’ issues (limited featureset) • Expensive