“…In particular, we observe that the state-of-the-art Newton-type methods are based on the idea of exploiting the local information on the function f (x), obtained by investigating the second order derivatives. In the context of large scale problems, the latter task is pursued by computing at the outer iteration k the pair (d k , s k ) of promising search directions [5,7,8,14,17,20], by means of efficient iterative techniques. Roughly speaking, d k summarizes the local convexity of f (x) at the current iterate, while s k takes into account the local nonconvexity of the objective function.…”