47. The computer program of claim 20 , wherein selecting the matched data cluster from among one or more existing data clusters includes selecting the matched data cluster from among multiple candidate data clusters for which the selected data record satisfies a cluster membership criterion.
47. The computer program of claim 20 , wherein selecting the matched data cluster from among one or more existing data clusters includes selecting the matched data cluster from among multiple candidate data clusters for which the selected data record satisfies a cluster membership criterion. 48. The computer program of claim 47 , further including instructions for causing a computing system to store information identifying one or more candidate data clusters that were not selected as the matched data cluster for the selected data record.