1. Tagging Systems Austin Wester

2. Tags A keywords linked to a resource (image, video, web page, blog, etc) by users without using a controlled vocabulary. They help to improve search, personal organization, metadata, spam detection, and reputation systems

3. Tag Purposes Social bookmarking Personal bookmarks Store and retrieve resources Social tagging systems Shared tags for particular resources Each tag is a link to additional resources tagged the same way by other users

4. Examples of Tagging Systems Flickr: A site for sharing and viewing photos. It allows users to store and tag their personal photos, tag friends photos and create a contact list Del.icio.us: A “social bookmarking site.” It allows users to tag web pages for easy retrieval. CiteULike: This site allows users to tag citations and references, e.g. academic papers or books. Youtube: A collection of videos allowing users to view and share by placing tags on the videos. Last.fm: A music information database allowing members to tag artists, albums, and songs

5. A model

6. Issue with Vocabulary Users use different terms to describe the same resources Polysemy: A single word has multiple meanings Synonymy: Different words have the same meaning Abstraction: Resource can be tagged at different levels of abstraction Animal, dog, German Shepherd, Alsatian Different languages Missing context: Tags that have no real relation with the images Holiday, me, friends, a person’s name

7. Taxonomy of Tagging Systems System design and attributes How the characteristics of a tagging system effects the content, the tags and the usage Users How their incentives and motivations affect the tagging system

8. System Design and Attributes Tagging rights: A tag can be added or removed by the creator of the resource, a restricted group or everyone Tagging support: The mechanism of a tag entry Blind tagging: a user cannot see a resource’s tags added by others Viewable tagging: all tags are visible Suggestive tagging: the system suggests possible tags to the user Aggregation: System either allows duplicate tagging (bag-model) or they prevent it (set-model) Type of object: images, videos, songs, web pages, blogs, games, etc Source of Material: Resources that can be tagged can be anything on the web, provided by users or by the system Resource connectivity: links, groups etc. connecting resources other than tags Social connectivity: The connection between the users may result in localized folksonomies.

9. User Incentives and Motivations Future retrieval: To mark individual or a collection of resource items for later personal retrieval Contribution and sharing: To add to conceptual clusters for the use by others of either a known or unknown audience Attract attention: to draw others to their resources (common tags, spam tags) Self presentation: to leave a mark Express opinions: to share their opinions with others

10. My Research Flickr.com Image popularity vs. tags Is there any relation Flickr API

11. Related Work

12. Case Study: Flickr Flickr is a photo-sharing site that considers tags as a core element to the sharing, retrieval, navigation and discovery of user-contributed images. It allows users to upload their photos and share with the public. Users can tag, choose favorites, comment, join groups, send messages, create networks, explore etc. It contains user-contributed resources instead of global resources. It allows self-tagging instead of free-for-all tagging. The tags are aggregated in sets instead of bags. It affords blind-tagging instead of suggested-tagging This system design motivates people to tag. By Yahoo! Research Berkeley & UC Berkley School of Information

13. Flickr Tags Tags are not mandatory User can tag their friends’ photos. But within 58 million tags observed, the overwhelming majority are owner tags. A large group of people have very few distinct tags while a small group has extremely large sets of tags.

14. Tag vocabulary size across the set of users

15. Usefulness and importance of tags pair-wise Pearson correlation between The number of uploaded photos The count of user’s distinct tags The number of contacts designated by the user Flickr usage correlation

16. Growth of distinct tags 10 random users were chosen Frequent uploaders ( > 100 photos) Frequent taggers ( > 100 tags) The number of distinct tags were observed as the number of photos uploaded increased.

17. Growth of distinct tags

18. Vocabulary Formation Flickr allows social networks and interest groups. There is a huge potential for social influence in the development of tag vocabularies. People can follow updates from their contacts and this promotes constant tagging.

19. Tag Categories

20. Number of tags per photo in Flickr

21. Screenshot of the river metaphor. By Yahoo! Research Shows interesting tags during the current time period http://research.yahoo.com/taglines/

22. Conclusion Social tagging systems have the potential to improve many information systems problems. Tagging systems could be improved Preventing problems of meaning Finding relations between the tags (synonyms, abstractions) My research will be to see if there is any relationship between the popularity of an image and the tags used to describe it

23. QUESTIONS?