We analyse the herding phenomenon in the management style of Spanish equity funds. Using the methodology of Lakonishok et al. (1992) and Sharpe's style analysis (1992), we find interesting conclusions in the investment behaviour of fund managers, a barely-explored aspect, especially in the...

In the context of convex mixed integer nonlinear programming (MINLP), we investigate how the outer approximation method and the generalized Benders decomposition method are affected when the respective nonlinear programming (NLP) subproblems are solved inexactly. We show that the cuts in the...

In this paper, we investigate the use of DC (Difference of Convex functions) models and algorithms in the application of trust-region methods to the solution of a class of nonlinear optimization problems where the constrained set is closed and convex (and, from a practical point of view, where...

A stochastic model is proposed to take into account the effect of a weak external field associated to diffusion, a discrete Master Equation is written down for the spatial distribution of particles. Approximate solutions are found for the first two cumulants, and applied to an example of...

We present a stochastic study of a polymerization reaction model. Using the WKB approximation and the method of factorial cumulants it is shown that the relaxation time of the second factorial cumulant is half the macroscopic relaxation time. Furthermore the system exhibits a globally...