220 likes | 350 Views
O ozing out knowledge in human brains to the Internet. Lada Adamic School of Information University of Michigan. http:// www.ladamic.com. Knowledge In . Oozing out knowledge.
E N D
Oozing out knowledge in human brains to the Internet Lada Adamic School of Information University of Michigan http://www.ladamic.com
Knowledge In Oozing out knowledge ``Knowledge search is like oozing out knowledge in human brains to the Internet. People who know something better than others can present their know-how, skills or knowledge'' NHN CEO ChaeHwi-young “(It is) the next generation of search… (it) is a kind of collective brain -- a searchable database of everything everyone knows. It's a culture of generosity. The fundamental belief is that everyone knows something.” -- Eckart Walther (Yahoo Research)
can we identify experts? fragment of the Java Forum Q&A network Zhang, Ackerman, Adamic, WWW 2007
ego-network structure of a technical forum programming Adamic et al., WWW 2008
What can the network structure of Q&A forums tell us about interactions? Marc Smith: “This proves that marriage is more like wrestling than like programming” programming marriage wrestling Image: Eytan Bakshy
Does focusing more narrowly correlate with higher quality contribution? vs.
Does focusing more narrowly correlate with higher quality contribution? music diseases and conditions number of users in category (> 40 replies total) languages homework help math physics biology chemistry correlation between focus & % best Yes, for technical/factual categories
more focus ->higher quality? papers patents Q&A Wikipedia Adamic et al., First Monday 2010
persistence and quality • even the most active users have intermittent activity • intermittency negatively correlated with quality Nam, Ackerman, Adamic, CHI 2009
Why? • What motivates users to answer hundreds to thousands of questions? • From interviews of Naver (Korean Q&A site) participants • Altruism • Learning • Hobby • Business • Points
what to answer? • filling in the blanks: users select unanswered questions • correcting others: last answer picked as best most often
Many answers you can get for free…What do you need to pay for? TaskCN: popular Chinese Witkey site Jiang, Adamic, Ackerman, ICWSM 2008, EC 2009
Taskcn knowledge sharing community • Askers offer cash rewards for best “solution” to task
How virtual points & real bucks influence participation in Q&A forums
users learn to choose less competitive tasks av. # of competitors in task log(interval) between wins
Field experiment • Crowdsourcing: 120 translation tasks • all pay auction mechanism: participants contribute solutions, only 1 is selected to receive payment • price treatment: high, low • shill treatment: enter in our own solution as a user with or without prior success • results • monetary incentives incentivize spam(85% are machine translations) • higher pay yields better contributions • shills discourage other quality contributions Liu, Yang, Adamic, Chen
Q: can collaborative work yield better solutions than individual efforts? • individual ideas & exploration • merging the best • e.g. Netflix prize
for more info • Crowdsourcing and knowledgesharing: strategic user behavior on TaskCnYang, J., Adamic, L., Ackerman, M.S., EC2009 • Questions in, KnowledgeIn?Nam, K., Ackerman, M.S., Adamic, L., CHI 2009 • Competing to share expertiseYang, J., Adamic, L., Ackerman, M.S., ICWSM2008 • Examining knowledge sharing on Yahoo AnswersAdamic, L., Zhang, J., Ackerman, M.S., Knowledge Sharing and Yahoo Answers: Everyone knows something, WWW’08 • ExpertiseRank algorithms and evaluations Zhang, J., Ackerman, M.S., Adamic, L., Expertise Networks in Online Communities: Structure and Algorithms, WWW’07 Lada Adamic ladamic@umich.edu http://www-personal.umich.edu/~ladamic