Juan Fernández

We propose a characterization of mathematical experiments in terms of a setup, a process with an outcome, and an interpretation. Using a broad notion of process, this allows us to consider arithmetic calculations and geometric constructions as components of mathematical experiments. Moreover, we argue that mathematical experiments should be considered within a broader context of an experimental research project. Finally, we present a particular case study of the genesis of a geometric construction to illustrate the experimental use of hand drawings and computers in mathematical practice.

The aim of the present study was to assess the impact of past traumatic war experiences on preadolescents in the Gaza Strip, which could be useful for psychological intervention with current and future child victims. Participants were 521 preadolescents from United Nations Relief and Works Agency for Palestine Refugees in the Near East (UNRWA) schools, aged 11 and 13 years old. Sections I to IV from Iraqi Version-Arabic of Harvard Trauma Questionnaire was used to assess trauma experiences and Post-Traumatic Stress Disorder (PTSD). The results show that the preadolescents in the Gaza Strip witnessed the destruction of their homes and the murder of family members and friends. A quarter of the individuals assessed either suffered torture or witnessed others undergoing it, including sexual assaults. Almost half of them experienced a lack of food and clean water. The traumatic and torture experiences seriously affected preadolescents’ mental health as 26.29% met criteria for the diagnosis of PTSD. The data analysis revealed two PTSD modalities, with the severity of impact depending on whether social implications were involved. Further research is required to check whether these two modalities fit to PTSD and complex PTSD. Understanding the effects of past wars on preadolescents in Gaza and distinguishing between different PTSD types could enhance comprehension of the impacts of current attacks on child victims. It can also aid in determining the type of intervention needed to minimize the impact on the mental health of Palestinian youth, enhancing their resilience through psychological and social support.

This paper presents a method to compute a posteriori probability intervals when the initial conditional information is also given with probability intervals. The right way to make an exact computation is with the associated convex set of probabilities. Probability trees are used to represent these initial conditional convex sets because they greatly save the space required. This paper proposes a simulated annealing algorithm, which uses probability trees to represent the convex sets in order to compute the a posteriori intervals.

The multilinear extension of a cooperative game was introduced by Owen in 1972. In this contribution we study the Lovász extension for cooperative games by using the marginal worth vectors and the dividends. First, we prove a formula for the marginal worth vectors with respect to compatible orderings. Next, we consider the direct market generated by a game. This model of utility function, proposed by Shapley and Shubik in 1969, is the concave biconjugate extension of the game. Then we obtain the following characterization: The utility function of a market game is the Lovász extension of the game if and only if the market game is supermodular. Finally, we present some preliminary problems about the relationship between cooperative games and combinatorial optimization

Este trabajo examina cómo, para ocupar la tribuna vacante del filósofo-orador José Ortega y Gasset, el exiliado Eduardo Nicol elaboró el emergente problema contemporáneo de la relación entre retórica y filosofía. Esta cuestión atañe tanto al qué como al para qué de la filosofía. ¿Hay un “grado cero” retórico en el pensamiento? Y si existe, ¿es el grado óptimo, considerando la meta humana de la filosofía? Nicol respondió ambas preguntas avanzando sobre la semiótica fenomenológica de Husserl, para establecer en la comunicación humana la constitución simultánea de expresión, significación y objetividad; y renunciando a la brillantez ensayística de Ortega como paradigma de influencia cultural de la filosofía. Pero, en el primer camino, no extrajo todas las consecuencias de su expresionismo; en el segundo, hubo de admitir una norma retórica algo diferente del grado cero, ya que la humanidad estaba en peligro. El caso de Nicol, en diálogo con todas las corrientes de la filosofía contemporánea, reafirma el lugar central que en ellas viene ocupando la semiótica.

en este trabajo analizo las diversas interpretaciones que ha suscitado la teoría del conocimiento de Giordano Bruno a partir de la segunda mitad del siglo XX. El objetivo principal es destacar una serie de problemas fundamentales que han de ser superados si se quiere esclarecer adecuadamente el conjunto de la propuesta gnoseológica de Bruno, en concreto sus tesis relativas al estatuto y función de la facultad fantástica y sus productos, las imágenes. Son tres los problemas destacados: la confusión terminológica que por parte de los intérpretes se observa en torno al concepto “imago”, en su doble sentido ontológico y gnoseológico; la tesis de que los productos mentales carecen de rasgos lógicos, idea a su vez derivada de una interpretación en exceso idealista de la génesis del conocimiento y la tesis de la “inmanencia fantásica”, consistente en reducir toda actividad gnoseológica al ámbito de la fantasía. Para justificar la problematicidad inherente a estas ideas acudiré tanto al texto bruniano como a la conocida distinción escolástica entre “concepto formal” y “concepto objetivo”.