This paper presents an historical analysis of relationship marketing. We discuss the roots and the directions of relationship marketing that are considered relevant: their origins, the Industrial Marketing and Purchasing group (IMP) approach to business relationships, the Nordic approach to...

The Expectation-Maximization (EM) algorithm is a very popular optimization tool for mixture problems and in particular for model-based clustering problems. However, while the algorithm is convenient to implement and numerically very stable, it only produces local solutions. Thus, it may not...