This paper addresses, from a mathematical programming point of view, t
he problem that consists in determining an hyperplane that separates,
as well as possible, two finite sets of points in R(n). In our formula
tion, a best separation hyperplane minimizes the number of misclassifi
ed points. A new mixed integer formulation of this problem is proposed
, together with a solution procedure based on implicit enumeration. Th
e formulation is characterized by a small integrality gap. Extensive n
umerical results on large scale problems (up to 300 points) are given
for both the exact algorithm and a derived heuristic procedure.