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See http://blogs.oii.ox.ac.uk/vis/ for details
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Interactive Visualizations For teaching, research, and dissemination
Scott A. Hale, Joshua Melville Kunika Kono
http://blogs.oii.ox.ac.uk/vis
Broad motivation
Proliferation of digital data (esp. geospatial and network)
The rise of ‘big data’, coupled with increasing interest in social media trace data
Many static, image-based visualizations being produced, with many tools geared up for producing them…
However, static images loose depth & sacrifice complexity and nuance
We concluded there is a lack of elegant, easy-to-use tools for non-technical researchers to create interactive visualizations
Existing tools, libraries
That is not to say that some tools do not already exist! For example:
Many Eyes
Google Charts, Maps
Simile Widgets
Sigma.js, D3.js
Miso
Raphael, Dojo Toolkit
oCanvas
Processing
Why interactive?
What are the limitations of conventional (static) approaches?
Logic of conventional visualization is a product of the limits of traditional paper-based dissemination methods. Cannot be interactive, by definition.
This reduces the intelligibility of complex data sets (by requiring inelegant and confusing visual representations)
…or forces simplification, resulting in a loss of explanatory power.
Multidimensionality of data (esp. ‘Big Data’) needs dynamic representation
This encourages user/reader exploration
Allows finding specific values without returning to source data
Promotes richer dissemination of findings outside of (and in addition to) traditional academic publication
Project development parameters
Browser native and standards compliant code
No flash, no java, no proprietary formats
Standalone/Offline
Can work in ebooks
Can work on tablets even if disconnected
Easy to use
Online interface to take the researcher “from datafile to visualization”
What types of visualizations?
Network diagrams
World choropleth maps
(Spatial treemaps)
Networks
Network data increasingly common
Structural explanation gaining momentum within social science
Influx of tools and techniques from other disciplines (Comp Sci/Physics)
SNA community has an historical aversion to disseminating raw data
A perceived complexity is seen to prevent the ‘lay’ interpretation of network data.
Nevertheless, visualization a crucial analytical/interpretive step.
Implementation Considerations
Computational Demands Hundreds/thousands of nodes to be rendered. Force directed layout algorithms scale poorly in javascript, and are difficult to implement. Interactivity adds further demands.
File Formats Many to choose from (graphml, gexf, gdf, dl, net). Some XML, some not. No clear winner.
Rendering Technology SVG, Canvas, WebGL…and the complex relationship between them.
Many Network Types – One (Extendable) Interface Need to avoid overly specific features/becoming a ‘twitter visualizer’.
Implementation Details
• Sigma.js as the renderer
• Renders to canvas element using its own internal drawing methods and scene management (layers for nodes, edges, etc.)
• HTML5/CSS3/JS interface, jQuery for transitions and effects
• Clean and customisable framework, based on a single json configuration file
• Editable by hand (for advanced users)
• Parser to turn common file formats into pure javascript data structures (json)
• Increases rendering speed
• Preserves existing layout (so no layout needed in browser)
Followers of @oiioxford
http://oxfordinternetinstitute.github.com/InteractiveVis/network/
https://apps.facebook.com/namegenweb/
OII Knowledge Exchange Project
Gephi Exporter Plugin
Issues/Limitations
No web based wizard (time constraints)
Upper bound to scalability due to rendering method
Potential to implement WebGL
Dependence on existing skills
Graph layout
Framing
Software packages (Gephi)
Maps
Point vs Choropleth/Polygon
While point maps are sexy, polygons are often easier to normalize
Static Literacy
Interactive Literacy
http://blogs.oii.ox.ac.uk/vis/?page_id=115
Knowledge Economies
Geotagged Tweets
http://blogs.oii.ox.ac.uk/vis/?page_id=115
Implementation
SVG/Raphael
Lightweight, standalone, tablet-friendlish
Abstracted json configuration
config in one place, human readable
setup wizard only needs to write two files (data, config)
http://api.oii.ox.ac.uk/InteractiveVisBuilder/
Issues/Limitations
Wizard UI wanting
Hard to mash up with GIS shapefiles
Unable to having backing/tile map
Possibly extend with leaflet.js implementation, but issues with speed portability.
Thanks!
Use the tools / contribute (all code is open source)
Sign up for our mailing list; subscribe to RSS feed
Extend the spirit of the project! Create your own class of visualisation, using open standards, and common data formats.
http://blogs.oii.ox.ac.uk/vis