Bipartite Cores (IMAGE) Carnegie Mellon University Caption In this graph of online auction transactions, the darkened oval represents a known perpetrator of fraud, while the other two ovals in the top row are suspected fraudsters. The bottom row of this graph, called a bipartite core, shows apparent accomplices who artificially boosted the fraudsters' reputation scores. Credit Carnegie Mellon University Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.