4. Purpose of data mining

Databases and data warehouses reach volumes of several terabytes (1 terabyte = 10 ¹² bytes). Major companies such as EDF, France Telecom and SFR collect several terabytes of customer consumption data every year. In a world of fierce competition, with the major telephone operators for example, knowledge of customers and their behavior enables us to better anticipate those who are likely to switch to a competitor, and to better adapt commercial operations to try and keep them. One of the major difficulties is knowing how to extract this profile from such a vast amount of data. Data mining offers, among other things, the means to analyze whether there is a typical behavioral profile of customers who change supplier. In this way, the company can more easily identify which of its customers have the profile to move to the competition, and then try...