Raghu Ramakrishnan

Professor

Computer Sciences Department
University of Wisconsin
1210 W. Dayton St.
Madison, WI 53706-1685

telephone: (608) 262-1204
fax: (608) 262-9777
email: raghu@cs.wisc.edu
http://www.cs.wisc.edu/~raghu/

Ph.D., University of Texas, Austin, 1987
Interests: Database query languages, data mining, integrated internet databases, and interactive information visualization.

Research Summary

My research currently centers on integrated access to internet databases, data mining, querying images by content, and interactive information visualization of very large distributed datasets.

As the use of databases grows and diversifies, especially on the internet, it is increasingly important to be able to access data from dispersed, heterogeneous, independently developed sources easily. The Gestalt project aims to develop a Publish-and-Register model in which integrators publish a description of desired data and data sources are independently registered into published "containers". This approach leads to integrated views over a very large number of sources, and gives rise to several challenges in structured search, change management, caching, and distributed query processing.

Prof. Livny and I are leading a visual data exploration project called DEVise that is developing a paradigm called visual templates, and allows a user to visually explore data sets much larger than available main memory. Each visual template is in essence an abstract description of how a collection of data is to be mapped to the user's screen. This work, which overlaps the Gestalt project, brings together research in the areas of visualization, database query processing, and WWW data access.

I also lead the PIQ project, whose goal is to support content-based retrieval from large sets of images. Our focus is on developing and implementing a general image database system with an expressive data definition language (DDL), and we are collaborating with Prof. Ramesh Jain at UCSD. The DDL definitions of a given collection of images guide how feature extraction, indexing and querying of that image collection are to be carried out.

In the area of data mining, I lead the DEMON project, which studies clustering and classification, particularly in the context of continuously evolving data, and the use of visual exploration techniques.

Sample Recent Publications

When is nearest neighbor meaningful? (with K. Beyer, J. Goldstein and U. Shaft), Proceedings of the International Conference on Database Theory, 1999.

RainForest: A Framework for fast decision tree construction of large datasets (with J. Gehrke and V. Ganti), Proceedings of the International Conference on Very Large Databases, 1998.

SRQL: Sorted relational query language (with D. Donjerkovic, A. Ranganathan, K. Beyer, and M. Krishnaprasad), Proceedings of the International Conference on Scientific and Statistical Database Management Systems, 1998.

This page was automatically created December 30, 1998.
Email pubs@cs.wisc.edu to report errors.