Wednesday, May 28, 2008

"Yes, There Is a Correlation"

This week I came across an interesting paper: "Yes, There is a Correlation - From Social Networks to Personal Behavior on the Web" by Parag Singla (University of Washington) and Matthew Richardson (Microsoft Research) in WWW'2008.

In summary, they show that the similarity between the personal interests and attributes of two users who are MSN contacts is much higher than two random users. Moreover, I've found the problem formulation elegant and the scale of data non-trivial to handle (approx. 13 million unique users).

From the paper:

Summarizing the results, we showed that people who talk to each other on the messenger network are more likely to be similar than a random pair of users, where similarity is measured in terms of matching on attributes such as queries issued, query categories, age, zip and gender. Further, this similarity increases with increasing talk time. The similarities tend to decrease with increasing average time spent per message. Also, we showed that even within the same demographics, people who talk to each other are more likely to be similar. Finally, as we hop away in the messenger network, the similarity still exists, though it is reduced.

I wonder whether a similar level of correlation would be observed in online communities with other purposes, such as content-sharing (e.g. Flickr and YouTube).

Friday, May 16, 2008

OurGrid 4.0 released

Good news from the South! The OurGrid 4.0 is out.

In summary: OurGrid is an open source, free-to-join, peer-to-peer grid, where users trade computational resources. The loosely coupled computational infrastructure is ideal for the execution of embarrassingly parallel applications.

I am particularly glad with this release, as OurGrid has been a useful tool in my previous studies. I used it to analyze traces of activity of content sharing communities. OurGrid makes it easy to harness the idle times of our desktop machines and monitor the progress of the computations in a much easier way.

Next week I will definitely give a try on the new version (as we are still using version 3.3).

The new site looks great too. Congratulations, OurGrid Community! :-)

Thursday, May 15, 2008

Deep Water(*) at 45rpm

A bit about recent music experiences...

It has been a while, since I listened to the voice of Beth Gibbons. So, I recently indulged myself with the addition of a new record to my collection. The Portishead new album: Third. By record, I mean an LP. :-)

The immediate surprise after playing the first song was to hear some voices in Portuguese. For a moment, I thought that the record player switch was set to FM Radio on some independent radio station.

The second big surprise was that record sound dark, with very slow beats and bass sounds. After a couple of seconds, I noticed that the album is an 45 RPM LP, as opposed to the usual 33 RPM records (more popular today). A quick adjustment on the player rotation speed and voilá!.

Overall, Portishead's new album sounds quite different from the previous works. I feel that there is more emphasis on the drums, which is really nice. Beth Gibbons voice is more discrete than in her solo album or in the previous Portishead recordings.

In my opinion, the best song of the album so far is Magic Doors (side 4, as the package comes with 2 LPs). :-)

Unfortunately, I missed their Coachella's concert, but I hope to have another opportunity soon...

(*) Deep Water is one of the songs of the album. I think it would work as a nice title for it.