Networks from SNAP (Stanford Network Analysis Platform) Network Data Sets,     
Jure Leskovec http://snap.stanford.edu/data/index.html                         
email jure at cs.stanford.edu                                                  
                                                                               
EU email communication network                                                 
                                                                               
Dataset information                                                            
                                                                               
The network was generated using email data from a large European research      
institution. For a period from October 2003 to May 2005 (18 months) we have    
anonymized information about all incoming and outgoing email of the research   
institution. For each sent or received email message we know the time, the     
sender and the recipient of the email. Overall we have 3,038,531 emails between
287,755 different email addresses. Note that we have a complete email graph for
only 1,258 email addresses that come from the research institution.            
Furthermore, there are 34,203 email addresses that both sent and received email
within the span of our dataset. All other email addresses are either           
non-existing, mistyped or spam.                                                
                                                                               
Given a set of email messages, each node corresponds to an email address. We   
create a directed edge between nodes i and j, if i sent at least one message to
j.                                                                             
                                                                               
Dataset statistics                                                             
                                                                               
Nodes   265214                                                                 
Edges   420045                                                                 
Nodes in largest WCC    224832 (0.848)                                         
Edges in largest WCC    395270 (0.941)                                         
Nodes in largest SCC    34203 (0.129)                                          
Edges in largest SCC    151930 (0.362)                                         
Average clustering coefficient  0.3093                                         
Number of triangles     267313                                                 
Fraction of closed triangles    0.004106                                       
Diameter (longest shortest path)    13                                         
90-percentile effective diameter    4.5                                        
                                                                               
Source (citation)                                                              
                                                                               
J. Leskovec, J. Kleinberg and C. Faloutsos. Graph Evolution: Densification and 
Shrinking Diameters. ACM Transactions on Knowledge Discovery from Data (ACM    
TKDD), 1(1), 2007.                                                             
                                                                               
Files                                                                          
File    Description                                                            
email-EuAll.txt.gz  Email network of a large European Research Institution