What are some ways that data mining and analytics could be used to detect fraud in health insurance claims?

Driving around Massachusetts, you might notice an RV frequently parked in your neighborhood with Montana license plates. Perhaps it is someone visiting from out west, but it might also be a Massachusetts resident who bought the RV online and registered it in Montana, which has no sales tax. The RV owner saves thousands of dollars, but Massachusetts loses the tax revenue. This kind of fraud is illegal but difficult to catch. A Massachusetts state agency, for example, would not have access to Montana's vehicle registrations and would not be able to match them up against Massachusetts' tax forms or employment records. The data are there, but they are not integrated into big data that can be analyzed.