  This article assumes acquired the skills and expertise of a statistician in
unsupervised (NMF, k-means, SVD) and supervised learning (regression, CART,
random forest). What skills and knowledge do a statistician must acquire to
reach the "Volume" scale of big data? After a quick overview of the different
strategies available and especially of those imposed by Hadoop, the algorithms
of some available learning methods are outlined in order to understand how they
are adapted to the strong stresses of the Map-Reduce functionalities
