Website recommendation system, Steven Buss, Univ. Florida
Name connectus
Group Buss
Matrix ID 2247
Num Rows 512
Num Cols 394,792
Nonzeros 1,127,525
Pattern Entries 1,127,525
Kind Undirected Bipartite Graph
Symmetric No
Date 2009
Author S. Buss
Editor T. Davis
Structural Rank 458
Structural Rank Full false
Num Dmperm Blocks 8
Strongly Connect Components 256
Num Explicit Zeros 0
Pattern Symmetry 0%
Numeric Symmetry 0%
Cholesky Candidate no
Positive Definite no
Type binary
SVD Statistics
Matrix Norm 4.833412e+02
Minimum Singular Value 0
Condition Number Inf
Rank 456
sprank(A)-rank(A) 2
Null Space Dimension 56
Full Numerical Rank? no
Download Singular Values MATLAB
Download MATLAB Rutherford Boeing Matrix Market
This is a matrix from Steven Buss, for a website recommendation system (to
be called www.connectious.com).  Each row of the matrix is a unique user. 
Eachc olumn of the matrix is a web page.  A(i,j)=1 if user i has tagged   
web page j as favorable, and a 0 represents no opinion.  The data was     
obtained from digg.com.  Note that the matrix A*A' contains one           
connected component of size 342, and 170 singletons (nodes with no edges) 
This means that a group of 341 users share some interests, at least       
indirectly, and that there are 171 other users that share no interests    
at all with any other users (they have no pages in common with anyone).