Model-Driven Research in Social Computing Abstract: Research in Augmented Social Cognition is aimed at enhancing the ability of a group of people to remember, think, and reason. Our approach to creating this augmentation or enhancement is primarily model-driven. Our system developments are informed by models such as information scent, sensemaking, information theory, probabilistic models, and more recently, evolutionary dynamic models. These models have been used to understand a wide variety of user behaviors, from individuals interacting with social bookmark search in Delicious and MrTaggy.com to groups of people working on articles in Wikipedia. These models range in complexity from a simple set of assumptions to complex equations describing human and group behaviors. By studying online social systems such as Google Plus, Twitter, Delicious, and Wikipedia, we further our understanding of how knowledge is constructed in a social context. In this talk, I will illustrate how a model-driven approach could help illuminate the path forward for research in social computing and community knowledge building Bio: Ed H. Chi is a Staff Research Scientist at Google, working on the Google+ project. Very recently, Ed was the Area Manager and a Principal Scientist at Palo Alto Research Center's Augmented Social Cognition Group. He led the group in understanding how Web2.0 and Social Computing systems help groups of people to remember, think and reason. Ed completed his three degrees (B.S., M.S., and Ph.D.) in 6.5 years from University of Minnesota, and has been doing research on user interface software systems since 1993. He has been featured and quoted in the press, including the Economist, Time Magazine, LA Times, and the Associated Press. With 20 patents and over 80 research articles, his most well-known past project is the study of Information Scent — understanding how users navigate and understand the Web and information environments. Most recently, he leads a group of researchers at PARC to understand the underlying mechanisms in online social systems such as Wikipedia and social tagging sites. He has also worked on information visualization, computational molecular biology, ubicomp, and recommendation/search engines. He has won awards for both teaching and research. In his spare time, Ed is an avid Taekwondo martial artist, photographer, and snowboarder.

1. WikiSym 2011 | Closing Keynote
!
Model-Driven Research in Social Computing!
!
Ed H. Chi!
!
Google
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!
Work done while
at Palo Alto
Research Center
(PARC)!
!
!
2011-10-05 WikiSym 2011 Closing Keynote 1

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2011-10-05 WikiSym 2011 Closing Keynote 8

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2011-10-05 WikiSym 2011 Closing Keynote 39

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2011-10-05 WikiSym 2011 Closing Keynote 40

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K 798& 149& 13% 25& 28& 26& 25& 18& 20&
F% 9,410& 352& 1,231& 713& 1,468& 851& 25& 879& 411&
%
G 7,208& 260& 580& 415& 708& 769& 18& 879& 265&
%
M 5,517& 100& 400& 6,046& 463& 424& 20& 411& 265&
2011-10-05 WikiSym 2011 Closing Keynote 41

40. ;#@)'&(+'"7-%
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2011-10-05 WikiSym 2011 Closing Keynote
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2011-10-05 WikiSym 2011 Closing Keynote 43

42. B,(7/%M7'k$/%5C$",G%"2%!"&'()%R(,+'&'@(+'"7%
Scale! Time Unit! Band!
107 s! Months!
106 s! Weeks! Social!
105 s! Days!
104 s! Hours!
103 s! 10 min! Rational!
102 s! Minutes!
101 s! 10 seconds!
100 s! Seconds! Psychological!
10-1 s! 100 msec!
10-2 s! 10 msec! Biological!
2011-10-05 WikiSym 2011 Closing Keynote 44

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2011-10-05 WikiSym 2011 Closing Keynote 45