1. Measuring Reliability in Wikipedia Wen-Yuan Zhu 2007.11.13

2. Outline Introduction Some term of Wikipedia Basic concept of measuring reliability A way to measure reliability Conclusion Reference

3. Introduction Wikipedia is the most popular online cooperation cyclopedia it has rich phenomenon which is difference to internet network and common webs

4. Some term of Wikipedia

5. Some term of Wikipedia(2) feature article – to be considered to be the best articles in Wikipedia – as determined by Wikipedian – at present, there are 1683 featured articles

6. Some term of Wikipedia(3) if an article is a feature article, it will show the icon at right corner

7. Some term of Wikipedia(4) articles are reviewed at Wikipedia:Featured article candidates according to Wikipedia:Featured article criteria

8. Some term of Wikipedia(5) make sure that it meets all of the featured article criteria consensus must be reached that it meets the criteria

9. Some term of Wikipedia(6) articles that no longer meet the criteria can be proposed for improvement or removal at Wikipedia:Featured article review

10. Some term of Wikipedia(7) clean-up article – cleanup issues that this project covers may include wikification, spelling, grammar, tone, and sourcing – anyone can require to cleanup some page in Wikipedia:Cleanup

11. Some term of Wikipedia(8)

12. Basic concept of measuring reliability if the article has the higher link ratio, the article has the higher reliability this part referred to [2]

13. Basic concept of measuring reliability(2) class of terms

14. Basic concept of measuring reliability(3) relation between full name and short

15. Basic concept of measuring reliability(4) Relation between PageRank and Link-ratio

16. Basic concept of measuring reliability(5) it is not enough to measuring reliability only rely on linking data there are too many factors to influence reliability of article in Wikipedia

17. A way to measure reliability to use Bayesian statistic to model reliability in Wikipedia to use revision history to assess the reliability of article in Wikipedia this part referred to [3]

18. A way to measure reliability(2)

19. A way to measure reliability(3) article trust – trustworthiness of a version of an article fragment trust – trustworthiness of a fragment in a version of an article author trust – trustworthiness of an author

20. A way to measure reliability(4) is the version of an article is the trust value of the author who revised is the trust value of is the inserted content in by is the deleted content in by is the size of

21. A way to measure reliability(5)

22. A way to measure reliability(6) Dynamic Bayesian networks – to be defined by a pair is the graph structure of the network is the set of the network’s conditional density distributions

23. A way to measure reliability(7) from to, the state at the revision is represented as a quad the states satisfies the Markov property – since,

24. A way to measure reliability(8)

25. A way to measure reliability(9) to determine the posterior density distribution of is fully characterized by and

26. A way to measure reliability(10) the Beta distribution where is the beta function with and

27. A way to measure reliability(11)

28. A way to measure reliability(12) to assume let is the mean of then or

29. A way to measure reliability(13)

30. A way to measure reliability(14) featured articles – considered highly trustworthy clean-up articles – considered untrustworthy Normal articles – remaining articles

31. A way to measure reliability(15) administrators – registered authors – anonymous authors – blocked users –

32. A way to measure reliability(16) a set of English articles from the Geography category in Wikipedia in January 2006 50 featured articles 50 clean-up articles 768 normal articles manually classify

33. A way to measure reliability(17) U.S. National Forest in Wikipedia created by an anonymous author

34. A way to measure reliability(18) is mean of the posterior density distribution

35. A way to measure reliability(19) to developed a classifier based on aforementioned 50 featured articles and 50 clean-up articles the training set contains 100 pairs, where is the trust value of an article and is its class

36. A way to measure reliability(20) the learned rule for feature article is the test size of 200 new articles(48805 revisions) was evaluated the accuracy of prediction is 82%

37. A way to measure reliability(21) to use trust track to predict events

38. A way to measure reliability(22) the method has some problems – the reliability of author is not a constant – the test set of classifier is too small – what is the predicting standards of predict events

39. Conclusion An overview of Wikipedia and measuring reliability in Wikipedia to introduce some ways to measuring reliability in Wikipedia to realize difficult problems of measuring reliability in Wikipedia

40. Reference [1] http://en.wikipedia.org/ [2] D. McGuinness, H. Zeng, Pda Silva, LDing, DNarayanan, and MBhaowal. Investigation into trust for collaborative information repositories: A Wikipedia case study. In Proceedings of the Workshop on Models of Trust for the Web, 2006. [3] H. Zeng, M. Alhoussaini, L. Ding, R. Fikes, and D. McGuinness. Computing trust from revision history. In Intl. Conf. on Privacy, Security and Trust, 2006.