Multistate Anti-Terrorism Information Exchange
The Multistate Anti-Terrorism Information Exchange Program, also known by the acronym MATRIX, was a U.S. federally funded data mining system originally developed for the Florida Department of Law Enforcement described as a tool to identify terrorist subjects. The system was reported to analyze government and commercial databases to find associations between suspects or to discover locations of or completely new "suspects".
Source: Wikipedia — Multistate Anti-Terrorism Information Exchange (CC BY-SA 4.0)