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Web2.0 Applications

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A brief Introduction on what is WEB 2.0 and an overview on some applications of the Web2.0.
Blogs, Wikis and Collaborative Tagging/Folksonomies.

Publié dans : Technologie

Web2.0 Applications

  1. 1. Web 2.0 Applications Tutorial
  2. 2. What is Web 2.0?
  3. 3. Web 2.0: the term <ul><li>Coined by T. O’Reilly </li></ul><ul><ul><li>Used as a title for a series of conferences since 2004 </li></ul></ul><ul><li>Misleading </li></ul><ul><ul><li>No new designed version of the Web </li></ul></ul><ul><li>Impressive </li></ul><ul><ul><li>A simple ajax-based application now is called a Web 2.0 application </li></ul></ul>
  4. 4. Evolution NOT Revolution
  5. 5. Web 2.0 “compact” definition <ul><li>Web 2.0 is the network as platform, spanning all connected devices </li></ul><ul><li>Web 2.0 applications are those that make the most of the intrinsic advantages of that platform </li></ul><ul><ul><li>get better the more people use it </li></ul></ul><ul><ul><li>consume and remix data from multiple sources including individual users while providing their own data and services </li></ul></ul><ul><ul><li>create network effects through an &quot; architecture of participation ” </li></ul></ul><ul><ul><li>go beyond the page metaphor of Web 1.0 to deliver rich user experiences </li></ul></ul><ul><li>By Tim O’Reilly </li></ul><ul><ul><li>http://radar.oreilly.com/archives/2005/10/web_20_compact_definition.html </li></ul></ul>
  6. 6. Key aspects of Web 2.0 <ul><li>Openess </li></ul><ul><ul><li>User generated metadata </li></ul></ul><ul><li>Interaction </li></ul><ul><ul><li>Rich and interactive user interfaces </li></ul></ul><ul><li>Community/Collaboration </li></ul><ul><ul><li>Social networks </li></ul></ul><ul><li>The Web as “the global platform” </li></ul><ul><ul><li>Sharing of services & data </li></ul></ul>
  7. 7. Some Web 2.0 applications <ul><li>Blogs </li></ul><ul><li>Wikis </li></ul><ul><li>Collaborative tagging systems / Folksonomies </li></ul>
  8. 8. Blogs
  9. 9. Blog Definition <ul><li>Weblog = Web + Log </li></ul><ul><li>A diary available on the Web that is frequently updated and intended for general public consumption </li></ul>
  10. 10. Blog Features <ul><li>Classical </li></ul><ul><ul><li>Background subject </li></ul></ul><ul><ul><li>Content organized in posts presented in inverse chronological order </li></ul></ul><ul><ul><li>Multilple roles: author, commentator, reader </li></ul></ul><ul><ul><li>Asynchronous & asymmetric communication </li></ul></ul><ul><li>Extra </li></ul><ul><ul><li>Permalink </li></ul></ul><ul><ul><li>RSS feed </li></ul></ul><ul><ul><li>Trackback / Pingback </li></ul></ul>
  11. 11. Wikis
  12. 12. Wiki as a collaborative tool <ul><li>Web pages editing through the browser </li></ul><ul><ul><li>Replace HTML with an easier syntax or a editor WYSWYG </li></ul></ul><ul><li>Foster the creation of “au pair” online communities </li></ul><ul><ul><li>Users are at the same time authors and readers of the wiki pages </li></ul></ul>
  13. 13. Principles : a wiki is… <ul><li>Open </li></ul><ul><ul><li>Everybody can contribute </li></ul></ul><ul><li>Dynamic </li></ul><ul><ul><li>Automatic generation of links </li></ul></ul><ul><li>Incremental </li></ul><ul><ul><li>Each page can be always improved </li></ul></ul><ul><li>Simple </li></ul><ul><ul><li>HTML not mandatory </li></ul></ul><ul><li>Monitorable </li></ul><ul><ul><li>Previous versions are stored </li></ul></ul><ul><li>Uniform </li></ul><ul><ul><li>No distinction between author and reader </li></ul></ul>
  14. 14. Basic functionalities : a wiki provides… <ul><li>Editing and preview of pages </li></ul><ul><li>Recent changes list </li></ul><ul><li>History of versions </li></ul><ul><li>Comparison of versions and Rollback </li></ul><ul><li>Pages Index </li></ul><ul><li>Search </li></ul><ul><li>Easy links ( WikiWord e Link Pattern) </li></ul><ul><li>Backlinks </li></ul>
  15. 15. Access Levels <ul><li>(Leuf, B. & Cunningham, W., 2001) </li></ul>Restrictions Description Level Login in the PC Private system Personal Login in the network Members of the same LAN Firewalled Login for access into the wiki Resticted access for both browse and editing Members-only Login for editing and for browsing of some pages Some restricted pages Restricted Editing Gate Login for editing Public pages Restricted access Lockable None Orignal Wiki Fully open
  16. 16. Wiki trade-off <ul><li>Benefits </li></ul><ul><li>No distinction between author and reader </li></ul><ul><li>Automatic and bidirectional links </li></ul><ul><li>Fosters collaboration </li></ul><ul><li>Exploits the Web as a collaborative environment (no clients to install) </li></ul><ul><li>Limits </li></ul><ul><li>Content accuracy </li></ul><ul><li>Limited layout and graphics </li></ul><ul><li>No standard Wiki syntax </li></ul>
  17. 17. What do I need server-side? <ul><li>Web Server </li></ul><ul><ul><li>Apache, IIS </li></ul></ul><ul><li>Wiki Engine </li></ul><ul><ul><li>Rendering in HTML </li></ul></ul><ul><ul><li>CMS </li></ul></ul><ul><li>Storage System </li></ul><ul><ul><li>Database </li></ul></ul><ul><ul><li>Flat Files </li></ul></ul>WEB Server Markup Rendering Engine CMS Flat Files Database
  18. 18. Which wiki engine do I need? <ul><li>MediaWiki </li></ul><ul><ul><li>PHP </li></ul></ul><ul><ul><li>MySQL </li></ul></ul><ul><ul><li>GNU General Public License </li></ul></ul><ul><ul><li>Used in Wikipedia </li></ul></ul><ul><li>PmWiki </li></ul><ul><ul><li>Uses PHP scripting language </li></ul></ul><ul><ul><li>Flat file </li></ul></ul><ul><ul><li>GNU General Public License </li></ul></ul><ul><li>MoinMoin </li></ul><ul><ul><li>Implemented in Python </li></ul></ul><ul><ul><li>Flat file </li></ul></ul><ul><ul><li>GNU General Public License </li></ul></ul><ul><li>UseModWiki </li></ul><ul><ul><li>Perl programming language </li></ul></ul><ul><ul><li>Flat file </li></ul></ul><ul><ul><li>GNU General Public License </li></ul></ul>Wiki Matrix http://www.wikimatrix.org/
  19. 19. Collaborative Tagging
  20. 20. Folksonomy or Collaborative Tagging? <ul><li>Folksonomy </li></ul><ul><ul><li>Folk ” + “ Taxonomy ” (taxonomy of the people) </li></ul></ul><ul><ul><li>Broad or Narrow </li></ul></ul><ul><li>Collaborative Tagging </li></ul><ul><ul><li>Each user tag items individually that aggregate at at a higher level via a collaborative action </li></ul></ul><ul><ul><li>The creation of metadata is shifted from an individual professional activity to a collective endeavor </li></ul></ul>
  21. 21. Features <ul><li>Bottom-up (Created by Users) </li></ul><ul><li>No structure </li></ul><ul><li>No fixed vocabulary </li></ul><ul><li>No explicit relationships between terms </li></ul><ul><li>No authority </li></ul><ul><li>Distribution </li></ul><ul><li>Collaboration </li></ul>
  22. 22. What’s new? Collaboration <ul><li>You can tag items owned by others </li></ul><ul><li>Instant feedback </li></ul><ul><ul><li>All items with the same tag </li></ul></ul><ul><ul><li>All tags for the same item </li></ul></ul><ul><li>Communication through shared metadata </li></ul><ul><ul><li>Tight feedback loop </li></ul></ul><ul><ul><li>Negotiation about the meaning of the terms </li></ul></ul><ul><ul><ul><li>You could adapt your tags to the group norm </li></ul></ul></ul><ul><ul><ul><li>Never forced </li></ul></ul></ul>
  23. 23. Collaborative Tagging model User Resource Tag
  24. 24. Collaborative tagging trade-off <ul><li>Benefits </li></ul><ul><li>Reflects user vocabulary </li></ul><ul><li>Sensitive to knowledge drift </li></ul><ul><li>Creates a strong sense of community </li></ul><ul><li>Emerging consensus </li></ul><ul><li>Limits </li></ul><ul><li>Synonymy </li></ul><ul><li>Polysemy </li></ul><ul><li>Basic level variation </li></ul><ul><li>Low precision & recall </li></ul>
  25. 25. Collaborative Tagging applications <ul><li>Social Bookmarking </li></ul><ul><ul><li>Del.icio.us, Fuzzzy </li></ul></ul><ul><li>Social Media sharing </li></ul><ul><ul><li>Flickr, YouTube, Last.fm </li></ul></ul><ul><li>Social reference management </li></ul><ul><ul><li>CiteULike, Bibsonomy, Connotea </li></ul></ul><ul><li>Other… </li></ul><ul><ul><li>Library Thing, Upcoming, 43 things, … </li></ul></ul>
  26. 26. Taxonomy vs Collab.Tagging <ul><li>Hierarchical </li></ul><ul><ul><li>Parent/child & sibling relationship </li></ul></ul><ul><li>Exclusive </li></ul><ul><ul><li>The same item can not be in two distinct categories </li></ul></ul><ul><li>Top-down </li></ul><ul><ul><li>Established by an authority </li></ul></ul><ul><li>Flat </li></ul><ul><ul><li>No levels, order, explicit relationship </li></ul></ul><ul><li>Not Exclusive </li></ul><ul><ul><li>An item can be associated to many tags </li></ul></ul><ul><li>Bottom-up </li></ul><ul><ul><li>Created by users </li></ul></ul>
  27. 27. Ontology <ul><li>Differ from taxonomic approach </li></ul><ul><ul><li>Not just “stamp collecting” </li></ul></ul><ul><ul><li>Do not follow a rigid parent/child hierarchical structure </li></ul></ul><ul><ul><li>Terms may inherit meaning from more than one parent </li></ul></ul><ul><ul><ul><li>More complex relationship is maintained </li></ul></ul></ul><ul><ul><li>May add inference engines </li></ul></ul>
  28. 28. Collab.Tagging vs Ontology <ul><li>Domain </li></ul><ul><ul><li>Large corpus </li></ul></ul><ul><ul><li>Informal categories </li></ul></ul><ul><ul><li>Unstable entities </li></ul></ul><ul><ul><li>Unestricted entities </li></ul></ul><ul><ul><li>Unclear edges </li></ul></ul><ul><li>Participants </li></ul><ul><ul><li>Naive catalogers </li></ul></ul><ul><ul><li>No Authority </li></ul></ul><ul><ul><li>Uncoordinated users </li></ul></ul><ul><ul><li>Amateur users </li></ul></ul><ul><ul><li>critical mass needed </li></ul></ul><ul><li>Domain </li></ul><ul><ul><li>Small corpus </li></ul></ul><ul><ul><li>Formal categories </li></ul></ul><ul><ul><li>Stable entities </li></ul></ul><ul><ul><li>Restricted entities </li></ul></ul><ul><ul><li>Clear edges </li></ul></ul><ul><li>Participants </li></ul><ul><ul><li>Expert catalogers </li></ul></ul><ul><ul><li>Authoritative source of judgment </li></ul></ul><ul><ul><li>Coordinated users </li></ul></ul><ul><ul><li>Expert users </li></ul></ul><ul><ul><li>Not too many (in the development process) </li></ul></ul>
  29. 29. Research directions… <ul><li>Collaborative tagging fosters participation but lacks in accuracy </li></ul><ul><ul><li>Enhance current collaborative tagging systems with power of semantics </li></ul></ul><ul><li>Classical ontology development provides accuracy but lacks in participation </li></ul><ul><ul><li>Augment current ontologies with large-scale user participation </li></ul></ul>
  30. 30. Selected references <ul><li>O'Reilly, T.: What is Web 2.0 . (2005) </li></ul><ul><li>Leuf, B. & Cunningham, W.: The Wiki way: Quick collaboration on the Web. Upper Saddle River, NJ, USA: Addison Wesley. (2001) </li></ul><ul><li>Speller, E.: Collaborative tagging, folksonomies, distributed classification or ethnoclassification: a literature review . Library Student Journal. (2007) </li></ul><ul><li>Golder, S. A., Huberman, B. A., The Structure of Collaborative Tagging Systems . ( 2005) </li></ul><ul><li>Gendarmi,D., Abbattista,F. and Lanubile,F.: Fostering knowledge evolution through community-based participation . Workshop on Social and Collaborative Construction of Structured Knowledge at WWW’07, (2007) </li></ul><ul><li>Gendarmi,D. and Lanubile,F.: Community-Driven Ontology Evolution Based on Folksonomies . Community Informatics Workshop at OTM’06, (2006) </li></ul>