A linear-dependence-based approach to design proactive credit scoring models

The main aim of a credit scoring model is the classification of the loan applicants into two classes, reliable and non-reliable customers, on the basis of their potential capability to keep up with their repayments. Nowadays, credit scoring models are increasingly in demand, due to the consumer credit growth. Such models are usually designed on the basis of the past loan applications and used to evaluate the new ones. Their definition represents an hard challenge for different reasons, the most important of which is the imbalanced class distribution of data (i.e., the number of default cases is much smaller than that of the non-default cases), and this reduces the effectiveness of the most widely used approaches (e.g., neural network, random forests, and so on). The Linear Dependence Based (LDB) approach proposed in this paper offers a twofold advantage: it evaluates a new loan application on the basis of the linear dependence of its vector representation in the context of a matrix composed by the vector representation of the non-default applications history, thus by using only a class of data, overcoming the imbalanced class distribution issue; furthermore, it does not exploit the defaulting loans, allowing us to operate in a proactive manner, by addressing also the cold-start problem. We validate our approach on two real-world data sets characterized by a strong unbalanced distribution of data, by comparing its performance with that of one of the best state-of-the-art approach: random forests.