On the database marketing literature, it is common practice to summarize customers’ past behavior in terms of their Recency, Frequency and Monetary Value (RFM) characteristics. Recency is the time of most recent purchase, Frequency is the number of past purchases and Monetary Value is the average purchased amount per transaction. RFM variables constitute basic ingredients for the estimation of customer lifetime value. The traditional approach to the analysis of RFM variables considers a descriptive statistical analysis while, in scoring models, these variables enter as fixed regressors.