Monitoring the Behaviour of Credit Card Holders with Graphical Chain Models

Consumer credit is any of the many forms of commerce under which an individual obtains goods or services on condition of a promise to pay for their value, along with a fee (the interest), at some specific future date or dates. Consumer credit can take a variety of forms: bank loans, credit cards, retailer’s card, car finance schemes, etc. In industrialized countries, this form of credit has become an enormous business. It is estimated that in Italy in the first semester of 1999, the total amount of consumer credits has increased by about 27% over the corresponding period in the previous year. This growth is in line with a positive trend started in the second half of the 1990s. The need to cope with a vast demand for credits forced the credit grantors to implement automatic techniques for deciding whether to grant an application or not. Different information, coming from application forms, records of past behaviour and