In the given research we study a leadership formation of the most influential nodes in networks. Specifically, we analyze the competition between a leader and a follower based on the Stackelberg leadership model. Applying the concept of Shapley value to measure node’s importance, we represent...

In terms of social networks, split graphs correspond to the variety of interpersonal and intergroup relations. In this paper we analyse the interaction between the cliques (socially strong and trusty groups) and the independent sets (fragmented and non-connected groups of people) as the basic...

Recently Beltrán-Royo, Vial & Alonso-Ayuso (2012) presented a semi-Lagrangean relaxation for the classical p-median location problem and for the incapacitated facility location problem. The results, obtained using the semi-Lagrangean relaxation approach, were quite impressive. In this paper we...

This paper simplifies, generalizes, extends, surveys and unifies results related to the efficient frontier in portfolio analysis and to asset pricing formulations of the Capital Asset Pricing Model (CAPM) type. It derives the composition and properties of many central portfolios in portfolio...

Betas computed from returns based on investment cost rather than on market value, may give systematically inappropriate discount rates and numerically incorrect present values for nonzero NPVs and "mispriced" assets. The paper provides a self contained collection of a "baker's dozen" consistent...