Archive for January, 2008

New swarming algorithm only tracks 7 neighbours

Thursday, January 31st, 2008

A new study of starling flocks has revealed that each bird only needs to track its nearest six or seven neighbours, regardless of their physical distance, to keep the flock cohesive. Previous models such as boids were based on each bird tracking every other bird within a certain range.

Library of Congress pics on flickr

Tuesday, January 29th, 2008

(by Franco Raimondi)

“… the Library of Congress has placed a few thousands of their pictures on flickr. From:
“If all goes according to plan, the project will help address at least two major challenges: how to ensure better and better access to our collections, and how to ensure that we have the best possible information about those collections for the benefit of researchers and posterity. In many senses, we are looking to enhance our metadata ”
The amazing pictures are here:

PhD Course on Social Network Analysis

Friday, January 25th, 2008

There is a course that is being run at the University of Kentucky on social network analysis. Other than having the course content online, including slides, it also has lots of pointers books, articles, and software: an interesting and useful resource for anyone  studying in the field.

Value of Social Networks

Tuesday, January 22nd, 2008

Metcalfe’s law describes the value of a network as being dependent on the number of users that participate in it (and also on an unknown constant of proportionality), and although the wikipedia example is about fax machines, this law could also be applied to social networks (and recommender systems). In other words, there must be some critical mass of users in the system for there to be any value in the system itself: what is this critical mass? Unfortunately it depends on how we define the cost per connection (new user) and value added by each connection. Can this be measured?

This post- written by Metcalfe himself- has a lot of interesting thoughts, including a combination of his law with Moore’s law and Anderson’s Long Tail, to show that as technology evolves, we get more value from less users (or the number of users in a network for the value to exceed its cost halves every two years!)

Free website hosting

Tuesday, January 22nd, 2008

The free saga continues. Lawrence Lessig is offering his latest book free, Chris Anderson is writing a new book “Free“, and now MS offers free¬† web hosting: “Microsoft UK is offering all Science, Technology, Engineering, Mathematics and Design students in the UK (email in domain) free web hosting for 1 year. Each student will have access to 500MB disk space on a Windows Server 2008/IIS 7 platform, with 1 x SQL 2005 database. The webspace will have support for ASP.NET 2.0, 3.0, 3.5, classic ASP, PHP 5 and CGI.” (I received it from a guy at MS Research Cambridge).

Benefits of Social Groups

Tuesday, January 22nd, 2008

There is an interesting article in Nature about group formation: the interactions between predators and prey (which was usually based on random mixing) is drastically changed when the predators and prey start forming social groups. Prey benefit from grouping by reducing the chances that predators will come across them, and predators benefit by being able to attack in numbers when they do encounter prey. Naturally, the question to ask is to what extent this could be true in other scenarios- (forming trust communities?) and can stability arise from being super-selective about who we interact with (thanks to Steve for the article).

Social Network Feedback in Real Time

Monday, January 21st, 2008

How people network during a meeting – and how the corresponding social network changes after lunch and after the last break. Nice pics in the original post.

Spam Dataset

Monday, January 21st, 2008

WEBSPAM-UK2007 ” is a large collection of annotated spam/nonspam hosts labeled by a group of volunteers. The base data is a set of 105,896,555 pages in 114,529 hosts in the .UK domain downloaded by the Laboratory of Web Algorithmics of the University of Milano. The assessment was done by a group of volunteers.

For the purpose of the Web Spam Challenge 2008, the labels are being released in two sets. SET1, containing roughly 2/3 of the assessed hosts will be given for training, while SET2 containing the remaining 1/3, will be held for testing. More information about the Web Spam Challenge 2008, co-located with AIRWeb 2008 will be available soon” here and here.

Search Engines and Mediocre Students

Friday, January 18th, 2008

There is an interesting article here about a university professor who bans her students from using Google and Wikipedia in their assignments, saying that they are “churning out banal and mediocre work by using what search engines provided them.” viagra usa She effectively argues that using search engines (and wikipedia) do not only offer students shallow (or potentially misleading) ideas, but also deprives them of interpretative and analytic skills. (more…)


Friday, January 18th, 2008

A short follow up to my recent post: Recently I’ve been reading Alvin Toffler’s Future Shock (written around 1970). It examines the accelerating rate of change in society, including the increased mobility of people, the evermore dynamic structures of organizations, and the impermanence of many aspects of life that may otherwise have been considered “points of reference” to people. Other than the fact that it’s usually fun to read what a futurologist of the past said about the future, apparently he is the one who coined the term “information overload;” a term he uses when describing a state where the prosperity of choice imprisons, rather than liberates, people. Here is a quote from the book: (more…)

Free book: The Future of Ideas

Thursday, January 17th, 2008

You can download The Future of Ideas by Lawrence Lessig free here (local pdf) or buy a (real) paper copy of it here.

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Openings (also on trust mng & ubicomp)

Friday, January 4th, 2008

The Security group at CNR in Pisa (Italy) has 5 openings for PhDs/PostDocs on those projects:

  • Context-aware Information Sharing
  • Security and Trust for GRID systems
  • Secure Software and Services for Mobile Systems
  • Biologically-inspired autonomic Networks and services
  • Software Engineering for Service-Oriented Overlay Computers
  • Secure and Resilient Networks and Services

Here is the full call. For more, please contact Fabio Martinelli.