Discovering telecom fraud situations through mining anomalous behavior patterns

Abstract

In this paper we tackle the problem of superimposed fraud detection in telecommunication systems. We propose two anomaly detection methods based on the concept of signatures. The first method relies on a signature deviation-based approach while the second on a dynamic clustering analysis. Experiments carried out with real data, voice call records from an entire week, corresponding to approximately 2.5 millions of CDRs and 700 thousand of signatures processed per day, allowed us to detect several anomalous situations. The frauds analysts provide us a small list of 12 customers for whom a fraudulent behavior was detected during this week. Thus, 9 and 11 fraud situations were discovered from each method respectively. Preliminary results and discussion with fraud analysts has already proved that our methods are a valuable tool to assist them in fraud detection. 1.