A hybrid system for fraud detection in mobile communication

During the course of the European project \Advanced Security for Personal Communication Technologies " (ASPeCT), we have developed some rule-based and neural network architectures as a number of di erent fraud detection tools for GSM networks. We have nowintegrated these di erent techniques intoahybrid detection tool. We optimized the performance of the hybrid system in terms of the number of subscribers raising alarms. More precisely, we optimized performance curves showing the trade-o between the percentage of correctly identi ed fraudsters versus the percentage of new subscribers raising alarms. We report here on a common suite of experiments we performed on these di erent systems. 1