[ ] SIENA

Stimulation Initiative for European Neural Applications

Esprit Project 9811



Case Studies of Successful Applications



Fraud detection in credit card transactions

Company background

SEMP is the company that deals with all the activities related to and originated by VISA credit cards issued by Spanish banks. A typical value of the total amount of such transactions is between 500.000 and 1.000.000 operations per day.

Description of the problem

The fight against fraud in transactions with VISA cards is obviously a problem of highest interest for SEMP. The main sources of fraud are theft and forgery of credit cards, and transactions with a higher economical impact must be processed on-line in order to obtain clearance. Systems with on-line capacity to detect if a transaction is fraudulent are therefore a prioritary objective for SEMP. The complexity of the inherent operation characteristics make very problematic the viability of rule-based applications. Besides, the changing nature of fraud would make specially difficult and expensive the maintenance of such a system.

Neural Networks techniques application

Distinction between a legal operation and a fraudulent one can be seen as a problem of two-category classification. Given the known ability of neural nets to carry out non linear classifications among sets, they have a natural application to the problem under consideration. The examples used in the construction of the detection model were taken from the analysis of the year 1994 and the first half of 1995 traffic on the operating sectors of main fraud impact (with a total of more than 3 million transactions). The net, developed in the "Instituto de Ingenieria del Conocimiento" (Knowledge Engineering Institute), implements what essentially is Fisher's discriminant analysis, after a non-linear transform of the detection variables.

Benefits

The natural measure of the system success is obviously its ability to decrease fraud, expressed as the resulting economical savings. The system assumes a decrease of fraud of about 30-40% on the main impact sectors.

Generalization

The detection problem considered here is characteristic of a wide family of decision problems for which the rule-based systems have difficult application and require expensive maintenance, while neural systems like the one described provide a fast construction of models and a relatively easy adaptation of these models to pattern changes. The applicability range of the techniques used in the SEMP problem is very wide, with particular interest in sectors like banking or insurance.

Contact person

Francisco Ginel, SEMP, c/. Gustavo Fernandez Balbuena 15, 28002 Madrid

References

C. Santa Cruz et al., "Hybrid neural methods in classification problems", IIC Technical Report 9501, Instituto de Ingenieria del Conocimiento, Universidad Autonoma, 28049 Madrid.