Category Archives: Uncategorized

On the cover of Neuron

Neuron coverWork by Olaf Sporns, YY Ahn, Alessandro Flammini and colleagues was featured on the cover of Neuron. In the paper Cooperative and Competitive Spreading Dynamics on the Human Connectome, the authors present a simulation model of spreading dynamics, previously applied in studies of social networks, that offers a new perspective on how the connectivity of the human brain constrains neural communication processes. Local perturbations in a social network can trigger global cascades (orange and turquoise epicenters in background image). In the case of the brain, the spreading of such cascades follows organized patterns that are shaped by anatomical connections revealing how interactions among functional brain networks may give rise to the integration of information.

Advice on grad school and the PhD

If you are contemplating grad school in general or applying for one of our PhD programs, and in particular if you are thinking about doing research with me, please take a look at these resources before you contact me:

NaN abstract for Le-Shin’s defense alpha

As adaptive peer network systems becoming an increasingly important development in Web search technology, in this research, an alternative model for peer based Web search is introduced to address the scale problem of centralized search engines. Queries are first matched against the local engine, and then routed to neighbor peers to obtain more results. Initially the network has a random topology (like Gnutella) and queries are routed randomly as in the flood model. However, the protocol includes a learning algorithm by which each peer uses the results of its interactions with its neighbors to refine a model of the other peers. This model is used to dynamically route queries according to the predicted match with other peers’ knowledge. The network topology is thus modified on the fly based on learned contexts and current information needs.

NaN talk for May 5, 2009: Mark Meiss, pre-Alpha Thesis Defense

This week at NaN I’ll be running through a very preliminary version of my thesis talk, “Structural Mining of Large-Scale Behavioral Data from the Internet,” which is all about the things you can discover using network flow data and Web clicks. The big things that I’ll be looking to get as feedback have to do with organization and pruning — I’m not terribly confident of the order in which I present the material, and I have a LOT more things to say than time to say it in, so I can use some suggestions on what to keep and what to just point to the actual document for.

(And, yes, there will be cookies.)

NaN abstract for Alejandro’s Defense Alpha

Online documents provide a rich information resource for aiding the generation of concept-map-based knowledge models, but analyzing resources to select concepts and links is a time consuming task.  This work focuses on harnessing the information in unstructured text documents using text mining algorithms to generate preliminary concept maps automatically.  These maps can be used to assist human users on question answering tasks or automatic document classification.

NaN Abstract for Michael Conover’s April 21st Talk

“The problem with Wikipedia is that it only works in practice. In theory, it can never work.”  — Zeroeth Law of Wikipedia

One of the most important social and intellectual phenomena of the 21st century, the collaboratively-edited online encyclopedia Wikipedia is vexing in its ability to produce informative articles on a multitude of subjects.  Leveraging graph theoretic techniques to measure the degree to which latent connections between articles are present in the Wikipedia corpus we demonstrate that the collaborative editing process produces, over time, an increasingly logically-connected information artifact. Moreover, using the public-domain 1911 Encyclopedia Britannica as a benchmark corpus for the single-author-article paradigm, we demonstrate that Wikipedia contains a growing core of mature articles which exhibit a degree of logical connectedness significantly surpassing that found in the Encyclopedia Britannica. Taken in conjunction with an understanding of Wikipedia’s accuracy and topical coverage, this conclusion paints a rich portrait of the strengths and weaknesses of both collaboratively- and single-author-edited encyclopedias.

AIRWEB 2009 practice talk for Tuesday, 3/24

Dear NaNers,

I will be using Tuesday (3/24) as a practice talk for AIRWEB 2009. Hope everyone had a nice spring break!

Title: Social Spam Detection

The popularity of social bookmarking sites has made them prime targets for spammers. Many of these systems require an administrator’s time and energy to manually filter or remove spam. Here we discuss the motivations ofsocial spam, and present a study of automatic detection of spammers in a social tagging system. We identify and analyze six distinct features that address various properties of social spam, finding that each of these features provides for a helpful signal to discriminate spammers from legitimate users. These features are then used in various machine learning
algorithms for classification, achieving over 98% accuracy in detecting social spammers with 2% false positives. These promising results provide a new baseline for future efforts on social spam. We make our dataset publicly
available to the research community.