Class Summary for October 2

   Group 2:
        Lauren Barton
        Martin Falck
           Nelson Kile
        Carolyn O'Hare
        Robert Ryan

   After our usual 40 minutes of fooling with the V-Tel system, 
we discussed the Ranking and Relevance feedback unit and the 
assignments for it as well as some administrative details.

   The next unit dealt with concepts of clustering.  Topics 
discussed were:
 - Centroids

 - Low level and hierarchical clustering

 - Uses with inverted file systems

 - Visualized with dendograms

 - Computing document to document similarity matrix and analyzing 
   its complexity

 - Algorithms using Minimal Spanning Tree and nearest neighbor 
   schemes

 - Steps in applying clustering

 - Clustering applications in IR systems - indexes

 - Measures of similarity - heuristics, formulas used for 
   computation, and some common measures

 - Space and time required for clustering algorithmss

 - Clustering algorithms - non-hierarchical vs hierarchical

 - Issues on updating the clusters 

 - Evaluation results