Jon Kleinberg CS lecture at U of T

Right now is the lecture by Jon Kleinberg, Department of Computer Science, Cornell University which is on Challenges in Mining Social Network Data: Processes, Privacy and Paradoxes. He has generated seminal results in social networks and document retrieval. I've read his research work on the HITS algorithm which uses hubs and authorities in order to classify search, and from which Google's PageRank is somewhat related to. I've never heard Jon speak so I'm very glad to hear him speak.

He will also speak tonight to kick off the Social Networking Week at U of T. What can computer science contribute to social networks? Today there is a convergence of social and technological networks, computing and information systems with intrinsic social structure. Social network data is a very active area in sociology, social psychology and anthropology. So what can the different fields learn from each other (sociology, social psychology, anthropology from computer science)? This is the research area which I am also part of as well, and it's an exciting research area in my opinion with the emergence of social networking sites like Facebook and MySpace. Mining social networks has a long history in social sciences eg. with Wayne Zachary's PhD work on the university karate club, observing social ties and rivalries. Split in the network could be explained by the minimum cut in the social network.

Social network data spans many orders of magnitude. For example there were 240 million nodes of all IM communication over one month on Microsoft Instant Messenger (Leskovec-Horvitz '07), 4.4 million nodes of declared friendships on blogging community LiveJournal (Liben-Nowell et al., 2005). How can we find the point where the lines of research in large scale and small scale networks converge? In social networks, we can find behaviours of diffusion in social networks that cascade from node to node like an epidemic, which is identified by radial structures in the graph. There have been empirical studies of diffusion in the social sciences like the spread of new agricultural and medical practices (Coleman et al., 1966). The diffusion curves are based on the probability of adopting new behaviour which depends on number of friends who have adopted (Bass 1969, Granovetter 1978 and Schelling 1978). All of the diffusion curves seem to have diminishing returns property, for example in editing a Wikipedia article (Cosley et al., 2007) and joining a LiveJournal community (Backstrom et al., 2006).

These results can then be used for general prediction. Given a network and v's position in it at t1, estimate the probability v will join a given group by t2. Kleinberg has formulated this as a probability estimation problem (Backstrom-Huttenlocher-Kleinberg-Lan 2006). Do disconnected friends or connected friends make joining more likely? Disconnected friends provide an informational advantage but connected friends provide safety/trust advantages. For example in LiveJournal, joining probability increases significantly with more connections among friends in the group (in otherwise friends that are within a clique than not).

If connectedness among friends promotes joining, do highly "clustered" groups grow more quickly? Kleinberg defines clustering to be # of triangles / # of open triads and you can determine community by examining the growth from t1 to t2 as a function of clustering. Leskovec, McGlohon, Faloutsos, Glance and Hurst (2007) have looked into the diffusion of topics in networks of news media and bloggers which shows cascading behaviour. Leskovec, Adamic and Huberman (2006) describe how incentives can be used to propagate interesting recommendations along social network links. How to push questions to people within the social network? (Kleinberg, Raghavan, 2005)

One of the most important questions in mining social network data is how to protect privacy in the dataset. There has been some research where anonymizing data actually caused problems from using on-line pseudonyms and using search engine query logs. If you are part of a small network and based on connectivity, you may be able to find yourself, so anonymization doesn't help. An attacker can attack an anonymized network by being part of the system. Kleinberg has done some work on this by creating a template (Backstrom, Dwork, Kleinberg, 2007). The idea is an attacker creates a small network of nodes through creating accounts called subgraph H and attach them to targeted nodes in the original network. From Ramsey theory, in a random n-node graph, H is unique.

Take home message: how do we build deeper models of the processes at work inside large-scale social networks? How do we make data available without compromising privacy?

It was great to finally meet and talk with Jon Kleinberg!

On Technorati: jon kleinberg, social network

Busy busy week this week

I've got a busy week ahead of me for this week. I'm giving an Ignite presentation about finding subgroups in TorCamp at DemoCampToronto15 tonight at Hart House, then have to finish marking assignments, then finish writing a paper, and then giving a talk at the Social Networking Week at U of T on Friday.

But I enjoy doing this kind of stuff, so I don't mind it. So don't expect too many blog entries this week!

Pervasive 2007 Conference trip report in IEEE Pervasive Computing magazine

Just found out that the Pervasive 2007 conference trip report which I helped co-author is now out in the IEEE Pervasive Computing magazine Vol. 6 No. 4 (October - December 2007). You can read the article here.

On Technorati: Pervasive2007

Finished my CASCON short paper talk

I just finished my CASCON short paper talk on "Identifying Active Subgroups in Online Communities" about an hour ago. It went well, I had some great feedback. I'll post the talk which I recorded and slides soon. Now, I can concentrate on the rest of my PhD work. No rest for a PhD student! But I enjoy giving talks and meeting with people and discussing about my research, it's exciting and engaging. If you have any comments or feedback from my paper or talk, write some comments on this blog back to me!

CASCON 2007 Conference, Day 1

I just finished co-chairing a session on Tagging as a Social Contract along with Mark Chignell and Sara Darvish, where we had 4 talks about issues surrounding tagging in a business environment. This was the second session as part of the Second Working Conference on Social Computing and Business at the CASCON 2007 conference. It was a great workshop and great session, and great discussion. I talked about how community can be inferred from tagging using the YouTube vaccination videos as an example. Podcasts and slides from the workshop should be available, so check the CASCON blog.

I also showed a demo of a community-based web portal that our lab created to support vaccination groups in our exhibit at the Technology Showcase called "Video Web 2.0: Collaborative Tagging in Web Video". If you're at CASCON, check it out!

Photos from CASCON are on my Flickr account.

Google hints at social network plan

I've been wondering when Google would start to think about social networking and how it could be used. So far, Yahoo has been the leader in social networking, with Flickr and Upcoming and Yahoo My Web Beta. Google's Orkut still does not compare in the same calibre with Facebook or MySpace, huge social networking web sites. However, Google is now beginning to hint how they will use social networking data in their own web search and to share the social data with others. According to Eric Schmidt, Google's CEO, from this article from NY Times, Google has something up its sleeve.

Will Google be able to top Yahoo and other social networking sites like Facebook? Only time will tell.

Passed the thesis proposal!

I just did my thesis proposal today and passed! Just need to make changes and do some more analysis and I should be hopefully done before April of next year.

Thesis proposal and busy rest of October!

I just finished writing the thesis proposal which I will send to my committee, because I will have a meeting with them on Wednesday. Hopefully, everything goes well and if everything goes according to plan, I can finish the dissertation and defence by end of this year!

It's going to be a busy rest of the October. I'm co-chairing a workshop at CASCON called Tagging as a Social Contract on Monday, October 22. If you're going to be at CASCON, sign up for this workshop, it promises to be an interesting one. For more information, check the CASCON blog. After that, I'm going to be presenting my paper at the CASCON conference on Wednesday, October 24 called "Identifying Active Subgroups in Online Communities". And then, I will be giving a talk at the Social Networking Symposium at U of T on Friday, November 2nd from 9:50 to 10:15 am called "Structural Analysis of Social Hypertext for Finding Sense of Community" right after my supervisor talks.

Married!

Yes, I just got married about a week ago, the wedding was great and the weather was just perfect. Couldn't have asked for a better day. Thanks to everyone who helped out in the wedding and for those that attended. My wife and I were so happy to see you there, and even though it was a tiring day, we thoroughly enjoyed it and will treasure this for the rest of our lives.

I'm very thankful this Thanksgiving for such a beautiful, amazing and considerate wife. And marriage life feels so great, I wouldn't trade it for anything else.

For those that are interested, I'll post wedding photos online soon.

Thanks for a great Hypertext conference!

I'd like to thank all the organizers for a great Hypertext conference! I thoroughly enjoyed it and meeting with lots of familiar faces and new ones. To remember the moments we shared together, I have placed all the photos that I took from the conference on my Flickr site. I had some people come to me to ask if I would put some notes from the talks on my blog. I'll do that when I have time and head back to Toronto.

See you all in Pittsburgh in Hypertext 2008!

On Technorati: Hypertext07, Hypertext2007

Day 2 of Hypertext conference

I'm at the Hypertext conference on Day 2. Some interesting talks on semantic web, web accessibility and user profiles. I'm really enjoying this conference, meeting lots of interesting work and interdisciplinary research. I'm going to present my research work tomorrow at 12 pm on Identifying Subcommunities Using Cohesive Subgroups in Social Hypertext. If you're at the conference, come and attend my talk!

More photos from yesterday and today are on Flickr.

On Technorati: Hypertext07

End of Day 1 session at Hypertext conference

Just finished the end of the technical sessions at the Hypertext conference, and am now in the Graduate BOF where there are lots of grad students chit chatting and just socializing. Then, there will be the SIGWEB business meeting and then the tour of the Manchester Museum.

Day 1 of Hypertext 2007 conference

Today is Day 1 of the Hypertext 2007 conference and I'm in Manchester, UK. Yesterday, I did my own tour around Manchester, going to the Whitworth Art Gallery and going to Curry Mile which is the Indian and Pakistanian area of Manchester of restaurants. Pictures of that and today's first day are available on Flickr.

Hypertext conference starts next week

There's only 4 days until the Hypertext conference starts in Manchester, England. It looks to be a great programme of papers and events. I'll be presenting my paper on "Identifying Subcommunities in Social Hypertext" on September 12 at 12 pm, yes right before lunch!

I look forward to meeting with people from last year's Hypertext which I presented, and meeting with new people.

On Technorati: hypertext07

Difference between social graph, social network web site, and social OS

Here's an article that explains what's the difference between a social graph, social network web site and social OS. An example of a social graph is the people connected to each other. AN example of a social network web site is Flickr or Twitter. An example of a social OS is Facebook, although I don't really kind of agree with that. I think of Facebook as a social network application or social network web site. It's not really an OS, because it doesn't permeate through all my computer's applications and it's not tied with Windows or Linux. All my applications I'm using do not all tie in with Facebook (at least not yet).

What do you all think about this?

Gmail redirects to garbled site

Yesterday, something strange happened. For some reason, when I went to Gmail, it would redirect me through ora.3168a.com to a garbled web page. I thought that I had contracted a virus or spyware, so I used Norton Antivirus and Lavasoft Ad-Aware to check, but found nothing. I tried to check Gmail with Internet Explorer, and it would also cause the same problem. I then cleared out the cache and history, and tried to access Gmail but I still got the garbled web page. This really puzzled me, so I tried to isolate the problem if it was a machine problem, by going to another computer and accessing Gmail from there. On another laptop, it was fine. Oh by the way, I was using Mozilla Firefox browser. But then when I went to another computer in the house, with Gmail, I still got the same redirect. What was worse was that not even Gmail but other web sites were redirecting through ora.3168a.com. Doing a Google search on ora.3168a.com resulted in a list of malicious and spam web sites of which ora.3168a.com was on the list.

I found out that another person also had the same problem as well, but apparently he was able to solve it by going through some several reboots and following some removal instructions translated from Japanese. I didn't do that, but today it seems like I can read Gmail now. It's kinda scary though what happened.

Social network web sites don't really social network

This article from Washington Post describes how social networking web sites like Facebook inundate us with more connections and actually alienate us than connect us. Duncan Watts feels that these web sites fail to do what they are supposed to do, which is "network". In a sense, I believe that he is right. When you social network, you meet with someone and start connecting and talking. With present social networking sites, it's more like just for getting in touch and updating your life to others. The number of social networking web sites are ballooning and multiplying like crazy. People really want to get on the social networking bandwagon, but they don't really understand the value of social networking.

On Technorati: social network

Prayers with the family and colleagues of Bill Richards

I just heard that Bill Richards, president of INSNA and long time contributor to social network analysis has just died. Apparently, he died of injuries sustained in a fall at his home. This is a great loss to the social networking community. I remember Bill as a vibrant person, full of energy, when I first met him at the Sunbelt conference in Vancouver last year. He also organized the hospitality suite at the conference at night where I remember talking with him. In the short time that I knew him, he came out as a sincere person and dedicated to his work and his graduate students.

Prayers and thoughts are with the Richards family, SFU, his grad students, colleagues and friends around the world. You will be surely missed Bill, but your charisma, energy and warmth will still remain with us.

On Technorati: Bill Richards, INSNA, social network analysis, Sunbelt

Did you know you can be banned from Facebook?

Well, I sure didn't until I read this post. Apparently, this guy tried to upload his 4600 contacts from Gmail into Facebook to allow invites, and then he got banned for unusual activity. I guess the Facebook application thought that he was a spammer uploading that many contacts. This then really begs the question, how does an application know that activity is spam or it is legitimate?

On Technorati: Facebook, banned

Howard Rheingold teaching virtual communities and social networks

Howard Rheingold, the author of The Virtual Community and Smart Mobs, is teaching at Stanford University this fall. His course is on Virtual Communities and Social Networks, in the Stanford Communication Department. The syllabus for the course is here.

Sounds interesting, the course material seems very relevant to what I'm doing. Students will be using social media technologies like forums, blogs, chat, etc. I'd be interested in attending this course if it was offered as a web cast, or even if there are lecture notes that I could download and have a look, as it is much related to my PhD research work on virtual communities.

On Technorati: Howard Rheingold, virtual community