Comunicaciones y ponencias de congresos DEIM - EIMS Biltzarretako komunikazioak eta txostenak

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Open Access
On the limits of effectiveness in estimation of distribution algorithms
(IEEE, 2011) Echegoyen Arruti, Carlos; Zhang, Qingfu; Mendiburu, Alexander; Santana, Roberto; Lozano, José Antonio; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika
Which problems a search algorithm can effectively solve is a fundamental issue that plays a key role in understanding and developing algorithms. In order to study the ability limit of estimation of distribution algorithms (EDAs), this paper experimentally tests three different EDA implementations on a sequence of additively decomposable functions (ADFs) with an increasing number of interactions among binary variables. The results show that the ability of EDAs to solve problems could be lost immediately when the degree of variable interaction is larger than a threshold. We argue that this phase-transition phenomenon is closely related with the computational restrictions imposed in the learning step of this type of algorithms. Moreover, we demonstrate how the use of unrestricted Bayesian networks rapidly becomes inefficient as the number of sub-functions in an ADF increases. The study conducted in this paper is useful in order to identify patterns of behavior in EDAs and, thus, improve their performances.
Open Access
Avatarians: playing with your friends' data
(Association for Computing Machinery, 2012) Marzo Pérez, Asier; Ardaiz Villanueva, Óscar; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Gobierno de Navarra / Nafarroako Gobernua
This article describes a new game mechanic called Game Entity Social Mapping (GESM) based on using social networking data fetched from a remote site about the player and his contacts to create characters, items or scenarios. A preliminary evaluation consisting of applying this mechanic to three different games was conducted. A small number of users tested those games to measure the enjoyment and learning about their contacts information.
Open Access
Significados conflictivos de ecuación y función en estudiantes de profesorado de secundaria
(Universidad de Salamanca, 2014) Wilhelmi, Miguel R.; Godino, Juan D.; Lasa Oyarbide, Aitzol; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika
En el marco de una acción formativa sobre reconocimiento de las características del razonamiento algebraico elemental con estudiantes del máster de secundaria, especialidad matemáticas, se detecta que las nociones de función y ecuación interfieren la una en la otra. Así, en situaciones elementales en las que es preciso movilizar una función, identificando las variables independiente, dependiente y regla de correspondencia, los estudiantes interpretan la situación en términos de incógnitas y ecuaciones. Se describen algunas respuestas prototípicas de este fenómeno, el contexto y metodología de la investigación, así como algunas implicaciones para la formación de profesores.
Open Access
Impacto de las evaluaciones externas en el sistema educativo
(Federación Española de Sociedades de Profesores de Matemáticas, 2017) Abaurrea Larrayoz, Jaione; Lasa Oyarbide, Aitzol; Wilhelmi, Miguel R.; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika
En este trabajo se analiza el impacto que generan las evaluaciones externas en el sistema educativo. El análisis centra el interés en la evaluación PISA. Por un lado, se recogen publicaciones con las noticias más relevantes respecto a las puntuaciones de los alumnos españoles y, por otro lado, se examina el impacto que genera PISA en las leyes curriculares. Además de explicitar los cambios curriculares en España, se representan las reformas educativas llevadas a cabo en Perú y México con el fin de contrastar diferentes medidas para la mejora del sistema educativo.
Open Access
Formación activa del profesorado: uso de la transposición meta-didáctica en un curso GeoGebra
(Federación Española de Sociedades de Profesores de Matemáticas, 2017) Lasa Oyarbide, Aitzol; Wilhelmi, Miguel R.; Abaurrea Larrayoz, Jaione; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika
Ante la constancia de que, en la década de 2010, los cursos de formación continua del profesorado de matemáticas en una región en España no han tenido un impacto claro en la práctica docente real de los centros educativos en el ámbito científico-tecnológico, el Centro de Apoyo al Profesorado (CAP) de esta región solicita a investigadores de la Universidad un curso de formación con metodología activa. Se propone, por ello, el uso de La Transposición Meta-Didáctica (TMD) como modelo teórico para el diseño de un curso de GeoGebra que supere la instrucción técnica de la herramienta y se centre en su uso efectivo en el aula, dado que la sola maestría informática del usuario no garantiza la correcta gestión de un proceso de enseñanza y aprendizaje, y genera, además, diversos fenómenos y obstáculos didácticos. La formación se realiza durante el curso 2016/2017 sobre una muestra de docentes del Cuerpo de profesores de educación secundaria de la región. Los resultados de la experimentación apoyan el modelo teórico empleado: los docentes modifican, en distinto nivel, sus praxeologías en cuanto a las técnicas y tecnologías empleadas. Además, el investigador obtiene evidencias empíricas que cuestionan algunos aspectos de su teoría de referencia.
Open Access
El problema de la argumentación: una aproximación desde el EOS
(Universidad de Granada, 2017) Lasa Oyarbide, Aitzol; Wilhelmi, Miguel R.; Abaurrea Larrayoz, Jaione; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika
La clasificación clásica de argumentos en inductivos y deductivos limita la comprensión y gestión de los procesos de estudio en matemáticas. Los currículos oficiales no concretan con precisión qué tipo de argumentos son válidos, dificultando la labor del docente. Además, la introducción del software de geometría dinámica en el aula intensifica los momentos de ilustración de propiedades, modificando con ello el contrato didáctico y los criterios de aceptación de proposiciones. La idoneidad didáctica permite pues incorporar al análisis de la argumentación criterios ecológicos, mediacionales, de interacción, cognitivos y afectivos que dan coherencia a las prácticas operativas y discursivas.
Open Access
A generalization of the gravitational search algorithm
(Springer, 2017-05-19) Bustince Sola, Humberto; Minárová, María; Fernández Fernández, Francisco Javier; Sesma Sara, Mikel; Marco Detchart, Cedric; Ruiz-Aranguren, Javier; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC
In this work we propose a generalization of the gravitational search algorithm where the product in the expression of the gravitational attraction force is replaced by more general functions. We study some conditions which ensure convergence of our proposal and we show that we recover a wide class of aggregation functions to replace the product.
Open Access
Some properties and construction methods for ordered directionally monotone functions
(IEEE, 2017-08-24) Sesma Sara, Mikel; Marco Detchart, Cedric; Bustince Sola, Humberto; Barrenechea Tartas, Edurne; Lafuente López, Julio; Kolesárová, Anna; Mesiar, Radko; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC
In this work we propose a new generalization of the notion of monotonicity, the so-called ordered directionally monotonicity. With this new notion, the direction of increasingness or decreasingness at a given point depends on that specific point, so that it is not the same for every value on the domain of the considered function.
Open Access
Outcomes and features of the inspection of receiver tubes (ITR) system for improved O&M in parabolic trough plants
(American Institute of Physics, 2018) Olano, Xabier; García de Jalón, Alberto; Pérez, David; García Barberena, Javier; López, Javier; Gastón Romeo, Martín; Estadística e Investigación Operativa; Estatistika eta Ikerketa Operatiboa
Concentrated solar power (CSP) plants based on parabolic trough (PT), after several years since their commissioning, demand new operation and maintenance (O&M) developments. Particularly, the receiver tube´s potential degradation over time is a real challenge. In this paper, the current version of the ITR System's last developments and advanced features are presented together with the main outcomes provided by the system for a real, complete solar field inspection in a commercial PT power plant. Exemplarily, this commercial ITR inspection showed that 0.8% of the tubes were underperforming and thus classified as outliers, while the average relative power of the tubes from the solar field resulted in about 97% of the ideal tubes' power. This paper shows that, thanks to the ITR Inspection System, plant operators can more easily develop and adopt improved O&M strategies, such as corrective and preventive actions in the solar field and even predictive actions in case of periodic inspections.
Open Access
Design exploration prior to blade multi-disciplinary optimisation
(IOP Publishing, 2018) Echeverría Durá, Fernando; Mallor Giménez, Fermín; San Miguel, Unai; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika
The approach of designing blades as a multi-disciplinary, holistic optimisation implies significant challenges owing to the high complexity of the involved factors such as aerodynamics, elasticity, controller and loads. Moreover, the large number of design variables complicates the intuitive analysis of the relationship between the design variables and responses. This paper presents the design variable exploration prior to blade optimisation, which reveals certain design variable combinations that lead to undesirable dynamic load amplification. Statistical tools, such as multiple logistic regression and fast and frugal decision trees, are applied to identify the conditions causing the phenomenon and predict the possible appearance under new design variable combinations.
Open Access
Strengthened ordered directional and other generalizations of monotonicity for aggregation functions
(Springer, 2018) Sesma Sara, Mikel; Miguel Turullols, Laura de; Lafuente López, Julio; Barrenechea Tartas, Edurne; Mesiar, Radko; Bustince Sola, Humberto; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC; Estadística, Informática y Matemáticas; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
A tendency in the theory of aggregation functions is the generalization of the monotonicity condition. In this work, we examine the latest developments in terms of different generalizations. In particular, we discuss strengthened ordered directional monotonicity, its relation to other types of monotonicity, such as directional and ordered directional monotonicity and the main properties of the class of functions that are strengthened ordered directionally monotone. We also study some construction methods for such functions and provide a characterization of usual monotonicity in terms of these notions of monotonicity.
Open Access
Twofold binary image consensus for medical imaging meta-analysis
(Springer, 2018) López Molina, Carlos; Sánchez Ruiz de Gordoa, Javier; Zelaya Huerta, María Victoria; Baets, Bernard de; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika
In the field of medical imaging, ground truth is often gathered from groups of experts, whose outputs are generally heterogeneous. This procedure raises questions on how to compare the results obtained by automatic algorithms to multiple ground truth items. Secondarily, it raises questions on the meaning of the divergences between experts. In this work, we focus on the case of immunohistochemistry image segmentation and analysis. We propose measures to quantify the divergence in groups of ground truth images, and we observe their behaviour. These measures are based upon fusion techniques for binary images, which is a common example of non-monotone data fusion process. Our measures can be used not only in this specific field of medical imagery, but also in any task related to meta-quality evaluation for image processing, e.g. ground truth validation or expert rating.
Open Access
A study of different families of fusion functions for combining classifiers in the one-vs-one strategy
(Springer, 2018) Uriz Martín, Mikel Xabier; Paternain Dallo, Daniel; Jurío Munárriz, Aránzazu; Bustince Sola, Humberto; Galar Idoate, Mikel; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika
In this work we study the usage of different families of fusion functions for combining classifiers in a multiple classifier system of One-vs-One (OVO) classifiers. OVO is a decomposition strategy used to deal with multi-class classification problems, where the original multi-class problem is divided into as many problems as pair of classes. In a multiple classifier system, classifiers coming from different paradigms such as support vector machines, rule induction algorithms or decision trees are combined. In the literature, several works have addressed the usage of classifier selection methods for these kinds of systems, where the best classifier for each pair of classes is selected. In this work, we look at the problem from a different perspective aiming at analyzing the behavior of different families of fusion functions to combine the classifiers. In fact, a multiple classifier system of OVO classifiers can be seen as a multi-expert decision making problem. In this context, for the fusion functions depending on weights or fuzzy measures, we propose to obtain these parameters from data. Backed-up by a thorough experimental analysis we show that the fusion function to be considered is a key factor in the system. Moreover, those based on weights or fuzzy measures can allow one to better model the aggregation problem.
Open Access
EEG-based endogenous online co-adaptive brain-computer interfaces: strategy for success?
(IEEE, 2018) Scherer, Reinhold; Faller, Josef; Sajda, Paul; Vidaurre Arbizu, Carmen; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika
A Brain-Computer Interface (BCI) translates patterns of brain signals such as the electroencephalogram (EEG) into messages for communication and control. In the case of endogenous systems the reliable detection of induced patterns is more challenging than the detection of the more stable and stereotypical evoked responses. In the former case specific mental activities such as motor imagery are used to encode different messages. In the latter case users have to attend sensory stimuli to evoke a characteristic response. Indeed, a large number of users who try to control endogenous BCIs do not reach sufficient level of accuracy. This fact is also known as BCI “inefficiency” or “illiteracy”. In this paper we discuss and make some conjectures, based on our knowledge and experience in BCI, on whether or not online co-adaptation of human and machine can be the solution to overcome this challenge. We point out some ingredients that might be necessary for the system to be reliable and allow the users to attain sufficient control.
Open Access
Image feature extraction using OD-monotone functions
(Springer, 2018) Marco Detchart, Cedric; López Molina, Carlos; Fernández Fernández, Francisco Javier; Pagola Barrio, Miguel; Bustince Sola, Humberto; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC; Estadística, Informática y Matemáticas
Edge detection is a basic technique used as a preliminary step for, e.g., object extraction and recognition in image processing. Many of the methods for edge detection can be fit in the breakdown structure by Bezdek, in which one of the key parts is feature extraction. This work presents a method to extract edge features from a grayscale image using the so-called ordered directionally monotone functions. For this purpose we introduce some concepts about directional monotonicity and present two construction methods for feature extraction operators. The proposed technique is competitive with the existing methods in the literature. Furthermore, if we combine the features obtained by different methods using penalty functions, the results are equal or better results than stateof-the-art methods.
Open Access
T-overlap functions: a generalization of bivariate overlap functions by t-norms
(Springer, 2018) Zapata, Hugo; Pereira Dimuro, Graçaliz; Fernández Fernández, Francisco Javier; Bustince Sola, Humberto; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC; Estadística, Informática y Matemáticas
This paper introduces a generalization of overlap functions by extending one of the boundary conditions of its definition. More specifically, instead of requiring that 'the considered function is equal to zero if and only if some of the inputs is equal to zero' , we allow the range in which some t-norm is zero. We call such generalization by a t-overlap function with respect to such t-norm. Then we analyze the main properties of t-overlap function and introduce some construction methods.
Open Access
Holistic architecture for music education: a proposal for empirical research in educational situations
(Universitat Politècnica de València, 2018) Ángel Alvarado, Rolando Alfredo; Wilhelmi, Miguel R.; Belletich Ruiz, Olga; Ciencias Humanas y de la Educación; Giza eta Hezkuntza Zientziak; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika
Holistic Architecture for Music Education (HAME) arises as a Design-Based Research, that is, it is an interdisciplinary research approach based on mixed research methods, which attempts understanding empirical phenomena from music education complexity. The HAME’ structural design poses a preliminary study of phenomena, the formulation of a research hypothesis, fieldwork in real-world situations and, finally, an analysis of data collected during the fieldwork with the intention of contrasting the hypothesis. This study aims to explore the technical suitability of the HAME in music education’s empirical research. Results demonstrate consistency between four phases of the structural design, in addition to prove the empirical complexity of organisational structures in music classrooms. In conclusion, the HAME is understood as an interdisciplinary educational research approach, which is holistically described as it connects theoretical currents of the social sciences and humanities with actual educational situations of music education. As a consequence, the HAME provides theoretical and practical knowledge about music education.
Open Access
On the influence of admissible orders in IVOVO
(Springer, 2019) Uriz Martín, Mikel Xabier; Paternain Dallo, Daniel; Bustince Sola, Humberto; Galar Idoate, Mikel; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC; Estadística, Informática y Matemáticas; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, PJUPNA13
It is known that when dealing with interval-valued data, there exist problems associated with the non-existence of a total order. In this work we investigate a reformulation of an interval-valued decomposition strategy for multi-class problems called IVOVO, and we analyze the effectiveness of considering different admissible orders in the aggregation phase of IVOVO. We demonstrate that the choice of an appropriate admissible order allows the method to obtain significant differences in terms of accuracy.
Open Access
Aggregation functions based on the Choquet integral applied to image resizing
(Atlantis Press, 2019) Bueno, Jéssica C. S.; Dias, Camila A.; Pereira Dimuro, Graçaliz; Santos, Helida; Bustince Sola, Humberto; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC; Estadística, Informática y Matemáticas
The rising volume of data and its high complexity has brought the need of developing increasingly efficient knowledge extraction techniques, which demands efficiency both in computational cost and in accuracy. Most of problems that are handled by these techniques has complex information to be identified. So, machine learning methods are frequently used, where a variety of functions can be applied in the different steps that are employed in their architecture. One of them is the use of aggregation functions aiming at resizing images. In this context, we introduce a study of aggregation functions based on the Choquet integral, whose main characteristic in comparison with other aggregation functions is that it considers, through fuzzy measure, the interaction between the elements to be aggregated. Thus, our main goal is to present an evaluation study of the performance of the standard Choquet integral the and copula-based generalization of the Choquet integral in relation to the maximum and mean functions, looking for results that may be better than the aggregation functions commonly applied. The results of such comparisons are promising, when evaluated through image quality metrics.
Open Access
On the influence of interval normalization in IVOVO fuzzy multi-class classifier
(Springer, 2019) Uriz Martín, Mikel Xabier; Paternain Dallo, Daniel; Bustince Sola, Humberto; Galar Idoate, Mikel; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC; Estadística, Informática y Matemáticas; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, PJUPNA13
IVOVO stands for Inverval-Valued One-Vs-One and is the combination of IVTURS fuzzy classifier and the One-Vs-One strategy. This method is designed to improve the performance of IVTURS in multi-class problems, by dividing the original problem into simpler binary ones. The key issue with IVTURS is that interval-valued confidence degrees for each class are returned and, consequently, they have to be normalized for applying a One-Vs-One strategy. However, there is no consensus on which normalization method should be used with intervals. In IVOVO, the normalization method based on the upper bounds was considered as it maintains the admissible order between intervals and also the proportion of ignorance, but no further study was developed. In this work, we aim to extend this analysis considering several normalizations in the literature. We will study both their main theoretical properties and empirical performance in the final results of IVOVO.