Spatial Database and Data Mining

Our group focusses on developing methods for storing querying, analyzing and mining very large geo-spatial datasets. For graph structured data (e.g. roadmaps), our group designed a novel storage method which is faster than traditional spatial indices. In querying area, our group has developed methods to process direction based predicates as well as methods to exploit parallel computers for answering spatial queries. In analysis and data mining, we are exploring computationally-efficient methods of modelling spatial auto-correlation which violates the independent identical distribution assumption made by data mining techniques based on classical statistics. We are exploring new data mining methods which can model auto-correlation and can scale up to large datasets.

Surveys are available from
1. Spatial Databases
2. Spatial Data Mining
powerpoint slides illustrating some of the projects are available at http://www.cs.umn.edu/~shekhar/talk .
Detailed technical slide presentations and research papers are available at http://www.cs.umn.edu/research/shashi-group .

Favourite Quotes: Computer Science Research

Barbara Liskov, ACM Turing Award (2009) in K. Frenkel, Liskov's Creative Joy, CACM, 52(7), July 2009: Liskov's advice for those wishing to pursue a career in research is to avoid taking a certain direction because it is likely to yield many published papers.Instead, she encourages following one's own star. "It's much better to go for the thing that's exciting," Liskov says. "But the question of how you know what's worth working on and what's not separates someone who's going to be really good at research and someone who's not. Threre is no prescription. It comes from your own intuition and judgement."
David Patterson, How to have a bad career in research/academia, 1994 OSDI keynote.
C. A. R. Hoare: There are two ways of constructing a software design; one way is to make it so simple that there are obviously no deficiencies, and the other way is to make it so complicated that there are no obvious deficiencies. The first method is far more difficult.

Favourite Quotes

Yogi Berra: In theory, there is no difference between theory and practice. But in practice, there is.
Arthur Schopenhauer (1788-1860): All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident.
Mahatma Gandhi:
- First they ignore you, then they laugh at you, then they fight you, then you win.
- Three quarters of the miseries and misunderstandings in the world would finish if people were to put on the shoes of their adversaries and understood their points of view.
- I have learned through bitter experience the one supreme lesson to conserve my anger, and as heat conserved is transmitted into energy, even so our anger controlled can be transmitted into a power that can move the world.