Research Interests

My research interests are in computational linguistics and natural language processing. These are closely related areas, but I see them as separate. Computational linguistics seeks to discover properties of human language via computational methods, while natural language processing develops tools and techniques that make it possible for computers to use and understand human language. In general the methods we develop are language and application independent, although we also have an interest in applying these to the medical domain.

We are engaged in three main areas of research right now, each of which in some way revolves around assigning meanings to words or phrases, or organizing words and phrases based on their semantic similarity to each other.

We are developing unsupervised methods of clustering similar contexts in the SenseClusters project. The goal is to develop methods that group together words or short phases based on their contextual similarity.
We are also developing methods that use the lexical database WordNet to assign similarity measurements to concepts ( WordNet::Similarity) and then use that information to carry out word sense disambiguation ( WordNet::SenseRelate). These methods are being extended to the medical domain via UMLS::Similarity.
Finally, I have a long standing interest in appplying supervised learning to the problem of word sense disambiguation, and that work continues.

Both the unsupervised and supervised methods rely heavily on lexical features that are identified from corpora using the Ngram Statistics Package.

I am always happy to involve motivated undergraduates in my research efforts. See my UROP page for more information.

Whenever possible, we like to take our systems and participate in shared tasks.

Active Research Projects:

..... SenseClusters ..... Ngram Statistics Package ..... WordNet::Similarity ..... UMLS::Similarity ..... WordNet::SenseRelate ..... Supervised WSD .....

Research Related Links:

........... Publications ........... Software ........... Data ........... NLP@UMD ........... Students ...........

Other Research Related Activities:

I review for conferences and workshops from time to time.

I was a member of the ACM SIGHIT Advisory Board (March 2011 - December 2012).

I was a member of the Scientific Board of SILT (Sustainable Interoperability for Language Technology) (2009 - 2011).

I gave a tutorial on Measuring the Similarity and Relatedness of Concepts in the Medical Domain at ACM IHI 2012 in Miami (with Serguei Pakhomov, Bridget McInnes, and Ying Liu).

I was the co-chair of a NAACL-HLT 2010 workshop (with Thamar Solorio). It was the Young Investigators Workshop on Compuational Approaches to Languages of the Americas.

I was an elected member (2009-2010) of the Executive Board of the North American Chapter of the Association for Computational Linguistics (NAACL) .

I gave the keynote talk at SETQA-NLP 2009 (a NAACL 2009 workshop) Didn't attend? See the slides and listen to the audio!

I was a member of the Editorial Board (2003-2005) of the journal Computational Linguistics .

I was the Secretary of the ACL Special Interest Group on Lexical Semantics (SIGLEX) (2004-2006)

I have co-organized two workshops on parallel text (at NAACL-2003 with Rada Mihalcea and at ACL-2005 with Joel Martin and Rada Mihalcea) and the interactive poster and demonstration session (at ACL-2005 with Masaki Nagata).

Rada Mihalcea and I gave a tutorial on Word Sense Disambiguation in 2004 and 2005.

I gave a tutorial on Unsupervised Clustering of Similar Contexts (i.e., SenseClusters) in 2005, 2006, and 2007.

We have interesting visitors at the NLP group at UMD every now and then.

I aspire to be an interesting visitor to other places from time to time.

Brian Rassier and I created and maintain the Registry of Latin American Researchers in NLP and CL.

The UMD Department of Computer Science has a Colloquia Series that I coordinated (2002-2005).

I am an academic great great great grandson of Wilfred Sellars. Here's how. You can also find me in the AI Genealogy Project.

By: Ted Pedersen - tpederse AT d umn edu