Jaime Gil Lafuente

A network-based data mining approach to portfolio selection via weighted clique relaxations

We introduce a new network-based data mining approach to selecting diversified portfolios by modeling the stock market as a network and utilizing combinatorial optimization techniques to find maximum-weight s-plexes in the obtained networks. The considered approach is based on the weighted market graph model, which is used for identifying clusters of stocks according to a correlation-based criterion. The proposed techniques provide a new framework for selecting profitable diversified portfolios, which is verified by computational experiments on historical data over the past decade. In addition, the proposed approach can be used as a complementary tool for narrowing down a set of “candidate” stocks for a diversified portfolio, which can potentially be analyzed using other known portfolio selection techniques.

Key factors for entrepreneurial success

Purpose – The purpose of this study is to explore the incidence between the actions to be taken by business promoters and the degree or level of success in creating new businesses. Design/methodology/approach – The paper matches data from market research based on a questionnaire sent to Spanish startups (years 2006-2010). The paper uses a methodology that is based on the “forgotten effects model”. Findings – Results show the elements that make up the target objectives are financing needs, marketing actions, continued innovation, and efforts in the areas of internationalization and sustainability. Originality/value – Using the forgotten effects model approach, this research tries to analyze the role that entrepreneurship actions play in the success of a projects objectives, taking into account not only the direct effects but also the indirect objectives.

The Best Systems for Appointing Referees

For many years, presidents and general managers of major football (soccer) clubs in Spain have been debating over how to assign referees for each match. When the responsible committee subjectively selected a referee, many people responsible for the “affected” teams had the right to complain about the always latent possibility that a certain amount of favoritism could occur for certain matches. While now, by using the famous “machine”1, the whims of randomness mean that certain matches that are considered important are not refereed by the most suitable referees.

New ideas on Marketing in Uncertainty

Planning and programming studies in a business generally start out from the knowledge of the possibilities that the market offers for absorbing goods and/or services. What is more, from a logical point of view, the processes of financing, investment, production etc., are conditioned by the possibilities of sales. This fact constitutes one of the reasons for development that can be seen both in the theory and in the techniques used for handling commercial problems.