Paired structures in knowledge representation.

In this position paper we propose a consistent and unifying view to all those basic knowledge representation models that are based on the existence of two somehow opposite fuzzy concepts. A number of these basic models can be found in fuzzy logic and multi-valued logic literature. Here it is claimed that it is the semantic relationship between two paired concepts what determines the emergence of different types of neutrality, namely indeterminacy, ambivalence and conflict, widely used under different frameworks (possibly under different names). It will be shown the potential relevance of paired structures, generated from two paired concepts together with their associated neutrality, all of them to be modeled as fuzzy sets. In this way, paired structures can be viewed as a standard basic model from which different models arise. This unifying view should therefore allow a deeper analysis of the relationships between several existing knowledge representation formalisms, providing a basis from which more expressive models can be later developed.

Improved solutions to dynamic and stochastic maritime pick-up and delivery problems using local search.

Heuristics for stochastic and dynamic vehicle routing problems are often kept relatively simple, in part due to the high computational burden resulting from having to consider stochastic information in some form. In this work, three existing heuristics are extended by three different local search variations: a first improvement descent using stochastic information, a tabu search using stochastic information when updating the incumbent solution, and a tabu search using stochastic information when selecting moves based on a list of moves determined through a proxy evaluation. In particular, the three local search variations are designed to utilize stochastic information in the form of sampled scenarios. The results indicate that adding local search using stochastic information to the existing heuristics can further reduce operating costs for shipping companies by 0.5–2 %. While the existing heuristics could produce structurally different solutions even when using similar stochastic information in the search, the appended local search methods seem able to make the final solutions more similar in structure.

Expansible Computable Aggregation Rules

The aggregation operator have been considered from a computable point of view. The important condition that the computation is friendly when portions of data are inserted o deleted to the list of values to aggregate is considered.

On the time to reach a critical number of infections in epidemic models with infective and susceptible immigrants.

In this paper we examine the time T to reach a critical number K0 of infections during an outbreak in an epidemic model with infective and susceptible immigrants. The underlying process X, which was first introduced by Ridler-Rowe (1967), is related to recurrent diseases and it appears to be analytically intractable. We present an approximating model inspired from the use of extreme values, and we derive formulae for the Laplace-Stieltjes transform of T and its moments, which are evaluated by using an iterative procedure. Numerical examples are presented to illustrate the effects of the contact and removal rates on the expected values of T and the threshold K0, when the initial time instant corresponds to an invasion time. We also study the exact reproduction number Rexact,0 and the population transmission number Rp, which are random versions of the basic reproduction number R0.

Tema 1. Distribuciones de probabilidad discretas (Curso 2011-2012)

Tema 1. Variables aleatorias discretas. Binomial. Poisson.

Tema 3. Contrastes de bondad de ajuste de variables discretas (Curso 2011-2012)

Contraste de Bondad de Ajuste de distribuciones discretas. Método de Chi-Cuadrado (para contrastar el ajuste a una Binomial).

Apuntes sobre la contribución española a las matemáticas

Este artículo pretende ofrecer una visión panorámica de la contribución original de los matemáticos nacidos en el actual territorio español durante el último milenio, analizando las causas de que dicha contribución haya sido inferior a la de países de tamaño, desarrollo económico y poder político semejantes.

Cáculo de estimadores de los Cuadrados Medios y Denominadores de la F

Cálculo estimadores CM y denominadores de la F en los análisis de ANOVA multifactorial.

Open business intelligence: on the importance of data quality awareness in user-friendly data mining

Citizens demand more and more data for making decisions in their daily life. Therefore, mechanisms that allow citizens to understand and analyze linked open data (LOD) in a user-friendly manner are highly required. To this aim, the concept of Open Business Intelligence (OpenBI) is introduced in this position paper. OpenBI facilitates non-expert users to (i) analyze and visualize LOD, thus generating actionable information by means of reporting, OLAP analysis, dashboards or data mining; and to (ii) share the new acquired information as LOD to be reused by anyone. One of the most challenging issues of OpenBI is related to data mining, since non-experts (as citizens) need guidance during preprocessing and application of mining algorithms due to the complexity of the mining process and the low quality of the data sources. This is even worst when dealing with LOD, not only because of the different kind of links among data, but also because of its high dimensionality. As a consequence, in this position paper we advocate that data mining for OpenBI requires data quality-aware mechanisms for guiding non-expert users in obtaining and sharing the most reliable knowledge from the available LOD.

Hacia la consideración de aspectos de calidad de datos en procesos de minería: el caso de las técnicas de clasificación

El éxito en la búsqueda de conocimiento a partir de grandes cantidades de datos radica en la calidad de los mismos. Hasta ahora los aspectos de calidad de los datos se han enfocado principalmente a la limpieza de los datos: detección de duplicados, valores atípicos, perdidos, incompletos o conflictos en instancias, entre otros. En este trabajo se presenta un caso de estudio que nos ha permitido determinar ciertos aspectos de calidad que pueden mejorar la expectativa de éxito en el análisis evitando resultados erróneos, incorrectos o poco fiables. Este es un primer paso hacia la consideración de manera sistemática y estructurada de criterios de calidad específicos para minería de datos que ayude al minero de datos en sus objetivos.

Towards a reverse engineering approach for guiding user in applying data mining

Comunicación presentada en las XVI Jornadas de Ingeniería del Software y Bases de Datos, JISBD 2011, A Coruña, 5-7 septiembre 2011.