1. A Classification-based Approach to Question Answering in Discussion Boards Liangjie Hong and Brian D. Davison Computer Science and Engineering Lehigh University Bethlehem, PA USA

2. Liangjie Hong and Brian D. Davison Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Outline

3. Liangjie Hong and Brian D. Davison How do you find answers on the Web? SIGIR July 2009 Motivation Motivation Problem Definition Features Experiments Conclusion

4. Liangjie Hong and Brian D. Davison Go to search engines… Motivation Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009

5. Liangjie Hong and Brian D. Davison Motivation Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Go to Question Answering Portals

6. Liangjie Hong and Brian D. Davison Motivation Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Go to discussion boards

7. Liangjie Hong and Brian D. Davison Motivation Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Why non-trivial?

8. Liangjie Hong and Brian D. Davison Motivation Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Why non-trivial? Comments, news, tutorials personal experiences

9. Liangjie Hong and Brian D. Davison Motivation Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Why non-trivial?

10. Liangjie Hong and Brian D. Davison Motivation Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Why non-trivial? Hello, I have a problem with my GUI not loading, it used to load and then i tried installing nvidia-glx from synpatics and then rebooted it removed a load of files but for some reason it wont go back to the gui so i remove nvidia-glx and installed nvidia-glx-180 with envyng -t when i do startx it goes to a black screen prior to this i couldnt even get to install glx-180 as it said missing files in the modules and everything but now i got past that, installed the driver, but still i cant get into the gui xserver is installed too as well as core

11. Liangjie Hong and Brian D. Davison Motivation Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Why non-trivial? Hello, I have a problem with my GUI not loading, it used to load and then i tried installing nvidia-glx from synpatics and then rebooted it removed a load of files but for some reason it wont go back to the gui so i remove nvidia-glx and installed nvidia-glx-180 with envyng -t when i do startx it goes to a black screen prior to this i couldnt even get to install glx-180 as it said missing files in the modules and everything but now i got past that, installed the driver, but still i cant get into the gui xserver is installed too as well as core No punctuation Spelling errors Mixed content … No punctuation Spelling errors Mixed content …

12. Liangjie Hong and Brian D. Davison Motivation Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 How does Google deal with forums?

13. Liangjie Hong and Brian D. Davison Motivation Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009

14. Liangjie Hong and Brian D. Davison Motivation Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009

15. Liangjie Hong and Brian D. Davison Motivation Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 How about

16. Liangjie Hong and Brian D. Davison Motivation Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009

17. Liangjie Hong and Brian D. Davison Motivation Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Not an answer

18. Liangjie Hong and Brian D. Davison Motivation Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Not an answer

19. Liangjie Hong and Brian D. Davison Problem Definition Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 What are “Questions” ?

20. Liangjie Hong and Brian D. Davison Problem Definition Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 What are “Questions” ? a sentence a sentence a paragraph a paragraph several paragraphs several paragraphs a post a post …

21. Liangjie Hong and Brian D. Davison Problem Definition Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 What are “Questions” ? a sentence a sentence a paragraph a paragraph several paragraphs several paragraphs a post a post …

22. Liangjie Hong and Brian D. Davison Problem Definition Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 What are “Answers” ?

23. Liangjie Hong and Brian D. Davison Problem Definition Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 What are “Answers” ? Hello, My problem is I can't find documentation on setting up a shared folder purely through the terminal. I know how to setup shared folders when there is a Gnome desktop on Ubuntu but my searches on this forum and Google haven't come up with instructions on how to do this purely through terminal commands. How do I add permissions to these folders for each user again purely through terminal commands? I plan on using Hardy since it's supported to 2013, but are there advantages to using Jaunty server instead that I'm not aware off? If someone can point me in the right direction on where I can find the information to set this up, it would be greatly appreciated. Thanks in advance for your help!

24. Liangjie Hong and Brian D. Davison Problem Definition Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 What are “Answers” ? Hello, My problem is I can't find documentation on setting up a shared folder purely through the terminal. I know how to setup shared folders when there is a Gnome desktop on Ubuntu but my searches on this forum and Google haven't come up with instructions on how to do this purely through terminal commands. How do I add permissions to these folders for each user again purely through terminal commands? I plan on using Hardy since it's supported to 2013, but are there advantages to using Jaunty server instead that I'm not aware off? If someone can point me in the right direction on where I can find the information to set this up, it would be greatly appreciated. Thanks in advance for your help! if you are using a ubuntu server and accessing it through windows workstations, you can simply install SAMBA, and then edit the smb.conf (the configuration file) through the terminal to set up file shares and permissions etc. as for users, you can simply create samba users and passwords (which could match your xp logins for simplicity)

25. Liangjie Hong and Brian D. Davison Problem Definition Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 What are “Answers” ? Hello, My problem is I can't find documentation on setting up a shared folder purely through the terminal. I know how to setup shared folders when there is a Gnome desktop on Ubuntu but my searches on this forum and Google haven't come up with instructions on how to do this purely through terminal commands. How do I add permissions to these folders for each user again purely through terminal commands? I plan on using Hardy since it's supported to 2013, but are there advantages to using Jaunty server instead that I'm not aware off? If someone can point me in the right direction on where I can find the information to set this up, it would be greatly appreciated. Thanks in advance for your help! if you are using a ubuntu server and accessing it through windows workstations, you can simply install SAMBA, and then edit the smb.conf (the configuration file) through the terminal to set up file shares and permissions etc. as for users, you can simply create samba users and passwords (which could match your xp logins for simplicity) Hello renzokuken..thanks for the quick response! So I could just install my server and setup my user id so I can login and administer the server. I don't need to setup userid's for each employee on the server. Instead I create samba users (which could be the userid of their windows PC's). I didn't know you could do this? I thought each user who used the share needed to have an Ubuntu login id?

26. Liangjie Hong and Brian D. Davison Problem Definition Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 What are “Answers” ? Hello, My problem is I can't find documentation on setting up a shared folder purely through the terminal. I know how to setup shared folders when there is a Gnome desktop on Ubuntu but my searches on this forum and Google haven't come up with instructions on how to do this purely through terminal commands. How do I add permissions to these folders for each user again purely through terminal commands? I plan on using Hardy since it's supported to 2013, but are there advantages to using Jaunty server instead that I'm not aware off? If someone can point me in the right direction on where I can find the information to set this up, it would be greatly appreciated. Thanks in advance for your help! if you are using a ubuntu server and accessing it through windows workstations, you can simply install SAMBA, and then edit the smb.conf (the configuration file) through the terminal to set up file shares and permissions etc. as for users, you can simply create samba users and passwords (which could match your xp logins for simplicity) Hello renzokuken..thanks for the quick response! So I could just install my server and setup my user id so I can login and administer the server. I don't need to setup userid's for each employee on the server. Instead I create samba users (which could be the userid of their windows PC's). I didn't know you could do this? I thought each user who used the share needed to have an Ubuntu login id? A couple of things to note. One is that Samba has a way to handle individual user (home dir) shares. The share is called [homes] and it is for all users. The second thing is where you are creating your mount point. Although you can create the mount point anywhere in the file system, I find that it makes more sense to keep the Samba shares under its own mount point. I use /smb

27. Liangjie Hong and Brian D. Davison Problem Definition Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 What are “Answers” ? Hello, My problem is I can't find documentation on setting up a shared folder purely through the terminal. I know how to setup shared folders when there is a Gnome desktop on Ubuntu but my searches on this forum and Google haven't come up with instructions on how to do this purely through terminal commands. How do I add permissions to these folders for each user again purely through terminal commands? I plan on using Hardy since it's supported to 2013, but are there advantages to using Jaunty server instead that I'm not aware off? If someone can point me in the right direction on where I can find the information to set this up, it would be greatly appreciated. Thanks in advance for your help! Hello renzokuken..thanks for the quick response! So I could just install my server and setup my user id so I can login and administer the server. I don't need to setup userid's for each employee on the server. Instead I create samba users (which could be the userid of their windows PC's). I didn't know you could do this? I thought each user who used the share needed to have an Ubuntu login id? A couple of things to note. One is that Samba has a way to handle individual user (home dir) shares. The share is called [homes] and it is for all users. The second thing is where you are creating your mount point. Although you can create the mount point anywhere in the file system, I find that it makes more sense to keep the Samba shares under its own mount point. I use /smb if you are using a ubuntu server and accessing it through windows workstations, you can simply install SAMBA, and then edit the smb.conf (the configuration file) through the terminal to set up file shares and permissions etc. as for users, you can simply create samba users and passwords (which could match your xp logins for simplicity)

28. Liangjie Hong and Brian D. Davison Problem Definition Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 What are “Answers” ? Hello, My problem is I can't find documentation on setting up a shared folder purely through the terminal. I know how to setup shared folders when there is a Gnome desktop on Ubuntu but my searches on this forum and Google haven't come up with instructions on how to do this purely through terminal commands. How do I add permissions to these folders for each user again purely through terminal commands? I plan on using Hardy since it's supported to 2013, but are there advantages to using Jaunty server instead that I'm not aware off? If someone can point me in the right direction on where I can find the information to set this up, it would be greatly appreciated. Thanks in advance for your help! Hello renzokuken..thanks for the quick response! So I could just install my server and setup my user id so I can login and administer the server. I don't need to setup userid's for each employee on the server. Instead I create samba users (which could be the userid of their windows PC's). I didn't know you could do this? I thought each user who used the share needed to have an Ubuntu login id? A couple of things to note. One is that Samba has a way to handle individual user (home dir) shares. The share is called [homes] and it is for all users. The second thing is where you are creating your mount point. Although you can create the mount point anywhere in the file system, I find that it makes more sense to keep the Samba shares under its own mount point. I use /smb if you are using a ubuntu server and accessing it through windows workstations, you can simply install SAMBA, and then edit the smb.conf (the configuration file) through the terminal to set up file shares and permissions etc. as for users, you can simply create samba users and passwords (which could match your xp logins for simplicity) Answer

29. Liangjie Hong and Brian D. Davison Problem Definition Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Questions & Answers Textual Mismatch ? Can any one help me load ubuntu 8.10 on to my pc? I have a asus AS V3-P5V900 but when i load from cd it keeps crashing, i think i does not reconise the graphics card. When i boot from cd it asks me what language ENGLISH then when try to load it crash again i have tried help and put in via=771 any help please? You might try using the “alternate” install CD: http://www.ubuntu.com/getubuntu/downloadmirrors#alternate

30. Liangjie Hong and Brian D. Davison Problem Definition Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 A Summary Two sub-tasks: Question detection Answer detection Our method: As a classification problem (not retrieval) Explore simple/combination features vs. NLP Better performance on two real world datasets

31. Liangjie Hong and Brian D. Davison Problem Definition Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 A Summary Two sub-tasks: Question detection Answer detection Our method: As a classification problem (not retrieval) Explore simple/combination features vs. NLP Better performance on two real world datasets The only page you need to remember

32. Liangjie Hong and Brian D. Davison Features Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 For questions Question mark (1 feature) 5W1H words (6) why, what, where, which, when, how Thread length (1) total number of posts Authorship (1) #first post/#total posts N-gram (1000-3000) Carvalho et al. Improving email speech acts analysis via n-gram selection. HLT/NAACL 2006.

33. Liangjie Hong and Brian D. Davison Features Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 For answers Post position (2) Authorship (1) N-gram (1000-3000) Stopwords (571) Query Likelihood Model (Language Model) (1)

34. Liangjie Hong and Brian D. Davison Experiments Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Datasets PhotographyOnTheNet ( http://www.photography-on-the.net/ ) 721, 442 threads UbuntuForums ( http://www.ubuntuforums.org ) 555, 954 threads Sampled approximately 500 threads for each sub-task and dataset

35. Liangjie Hong and Brian D. Davison Experiments Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Classification Method Manually labeled questions vs. non-questions one best answer per thread 10-fold cross validation libSVM for classification F-Measure Measured performance by Precision, Recall, F-Measure, Accuracy

36. Liangjie Hong and Brian D. Davison Experiments Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Comparisons to existing methods For questions Part-Of-Speech tagging Stanford Log-linear POS tagger Sequential Pattern Mining For answers Graph-based model incorporated with inter-posts relevance, authorship and similarity Cong et. al. Finding question-answer pairs from online forums. SIGIR 2008.

37. Liangjie Hong and Brian D. Davison Experiments Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Question Detection Single Feature (UbuntuForums)

38. Liangjie Hong and Brian D. Davison Experiments Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Question Detection Single Feature (Photography)

39. Liangjie Hong and Brian D. Davison Experiments Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Question Detection Combined Feature (UbuntuForums)

40. Liangjie Hong and Brian D. Davison Experiments Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Question Detection Combined Feature (Photography)

41. Liangjie Hong and Brian D. Davison Experiments Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Answer Detection Single Feature (Ubuntu)

42. Liangjie Hong and Brian D. Davison Experiments Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Answer Detection Single Feature (Photography)

43. Liangjie Hong and Brian D. Davison Experiments Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Answer Detection Combined Feature (UbuntuForums)

44. Liangjie Hong and Brian D. Davison Experiments Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Answer Detection Combined Feature (Photography)

45. Liangjie Hong and Brian D. Davison Conclusion Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Summary Question Detection N-gram Authorship+Question Mark+5W1H+Length Answer Detection Position, Authorship Position+Authorship Language Model+Position+Authorship

46. Liangjie Hong and Brian D. Davison Conclusion Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Summary Question Detection N-gram Authorship+Question Mark+5W1H+Length Answer Detection Position, Authorship Position+Authorship Language Model+Position+Authorship

47. Liangjie Hong and Brian D. Davison Conclusion Motivation Problem Definition Features Experiments Conclusion SIGIR July 2009 Thank you! Questions? Contact Info: Liangjie Hong hongliangjie@lehigh.edu WUME Laboratory Computer Science and Engr. Lehigh University Bethlehem, PA 18015 USA