Fuzzy clustering with entropy regularization for interval-valued data with an application to scientific journal citations

In recent years, the research of statistical methods to analyze complex structures of data has increased. In particular, a lot of attention has been focused on the interval-valued data. In a classical cluster analysis framework, an interesting line of research has focused on the clustering of interval-valued data based on fuzzy approaches. Following the partitioning around medoids fuzzy approach research line, a new fuzzy clustering model for interval-valued data is suggested. In particular, we propose a new model based on the use of the entropy as a regularization function in the fuzzy clustering criterion. The model uses a robust weighted dissimilarity measure to smooth noisy data and weigh the center and radius components of the interval-valued data, respectively. To show the good performances of the proposed clustering model, we provide a simulation study and an application to the clustering of scientific journals in research evaluation

Integration of the Wang & Mendel algorithm into the application of Fuzzy expert systems to intelligent clinical decision support systems

The use of intelligent systems in clinical diagnostics has evolved, integrating statistical learning and knowledge-based representation models. Two recent works propose the identification of risk factors for the diagnosis of obstructive sleep apnea (OSA). The first uses statistical learning to identify indicators associated with different levels of the apnea-hypopnea index (AHI). The second paper combines statistical and symbolic inference approaches to obtain risk indicators (Statistical Risk and Symbolic Risk) for a given AHI level. Based on this, in this paper we propose a new intelligent system that considers different AHI levels and generates risk pairs for each level. A learning-based model generates Statistical Risks based on objective patient data, while a cascade of fuzzy expert systems determines a Symbolic Risk using symptom data from patient interviews. The aggregation of risk pairs at each level involves a fuzzy expert system with automatically generated fuzzy rules using the Wang-Mendel algorithm. This aggregation produces an Apnea Risk indicator for each AHI level, allowing discrimination between OSA and non-OSA cases, along with appropriate recommendations. This approach improves variability, usefulness, and interpretability, increasing the reliability of the system. Initial tests on data from 4400 patients yielded AUC values of 0.74–0.88, demonstrating the potential benefits of the proposed intelligent system architecture.Xunta de Galicia | Ref. ED481A-2020/03

Járműdinamikai rendszerek integrált fuzzy-sztochasztikus modellezése és identifikációja = Integrated Modeling and Identification of Vehicle Dynamic Systems

A kutatómunka a lineáris és a nemlineáris járműdinamikai rendszerek a bizonytalansági tényezőket is figyelembe vevő új típusú modellezési eljárásainak és rendszeridentifikációs algoritmusainak kidolgozásával foglalkozik. A járműdinamikai modellezés metodológiai megközelítése a hagyományos statisztikai rendszeridentifikációs módszerek mellett alkalmazza a különböző lágy számítástudományi megközelítési módokat, így többek között felhasználja a fuzzy logika, fuzzy irányítástechnika algoritmusait, a neurális és fuzzy-neurális hálózatokat, továbbá a szinguláris értékdekompozíció (SVD) módszereit, kapcsolatot teremtve az LPV rendszereken értelmezett Takagi-Sugeno típusú fuzzy irányítási algoritmusok és a magasabb rendű szinguláris érték dekompozíció között. A nemlineáris járműdinamikai rendszerek komplex modellezésénél foglalkozunk a hatékony komplexitás csökkentő technikák kidolgozásával is, fuzzy interpolációs eljárások alkalmazásával, ahol a tömeges adatfeldolgozást multiprocesszoros számítások segítségével végezzük el. A lineáris járműdinamikai modellezés során összehasonlítjuk a szabályalapú fuzzy irányítástechnikai eljárásokkal kapott eredményeket a sztochasztikus identifikációs módszerek becslésével, a transzferfüggvények illetve a transzfermátrixok különböző típusú approximációja alapján. | This research project deals with the construction and development of new models of "uncertain principles" for the description of linear and nonlinear vehicle system dynamics using efficient new stochastic, fuzzy modelling approaches and identification algorythms. The methodological approach of the vehicle dynamics modelling is not only based on the traditional statistical system idetificaion methods, but on those soft computing approaches using among others fuzzy logic and fuzzy control algorythms, neural and fuzzy-neural networks, new singular value decomposition methods, establishing interconnection between Takagi-Sugeno type control models interpreted for LPV systems and higher order singular value decomposition (HOSVD). In the large-scale and complex modelling of the nonlinear vehicle system dynamics efficient complexity reduction techniques and fuzzy interpolative methods will be applied for the realization of the mass-data processing on the basis of multiprocessor computational intelligence. In the linear vehicle dynamic modelling a comparison will be examined between the rulebased fuzzy control approaches and modelling of the well-known modern stochastic identification methods on the basis of different transfer function and transfer matrix approximations

A Comparison of the performance of non-parametric classifies with Gaussian maximum likelihood for the classification of multispectral remotely sensed data

This study compares the performance of two non-parametric classifiers and Gaussian Maximum Likelihood (GML) for the classification of LANDSAT TM 30-meter resolution six-band data. The mathematical assumptions made in developing GML are valid if the pixels that constitute the training classes are normally distributed. Since it requires a model of the data, GML is termed a parametric classifier. Of current interest are new classification methodologies that make no assumptions about the statistical distribution of the pixels in the training class; these approaches are termed non-parametric classifiers. This study will compare the n-Dimensional Probability Density Function (nPDF) essentially a projection technique that reduces data dimensionality, and an advanced neural network that utilizes fiizzy-set mathematics, the Fuzzy ARTMAP, to the traditional GML approach to image classification. The different approaches will be compared for statistical classification accuracy and computational efficiency

A Genetic Tuning to Improve the Performance of Fuzzy Rule-Based Classification Systems with Interval-Valued Fuzzy Sets: Degree of Ignorance and Lateral Position

Fuzzy Rule-Based Systems are appropriate tools to deal with classification problems due to their good properties. However, they can suffer a lack of system accuracy as a result of the uncertainty inherent in the definition of the membership functions and the limitation of the homogeneous distribution of the linguistic labels. The aim of the paper is to improve the performance of Fuzzy Rule-Based Classification Systems by means of the Theory of Interval-Valued Fuzzy Sets and a post-processing genetic tuning step. In order to build the Interval-Valued Fuzzy Sets we define a new function called weak ignorance for modeling the uncertainty associated with the definition of the membership functions. Next, we adapt the fuzzy partitions to the problem in an optimal way through a cooperative evolutionary tuning in which we handle both the degree of ignorance and the lateral position (based on the 2-tuples fuzzy linguistic representation) of the linguistic labels. The experimental study is carried out over a large collection of data-sets and it is supported by a statistical analysis. Our results show empirically that the use of our methodology outperforms the initial Fuzzy Rule-Based Classification System. The application of our cooperative tuning enhances the results provided by the use of the isolated tuning approaches and also improves the behavior of the genetic tuning based on the 3-tuples fuzzy linguistic representation.Spanish Government TIN2008-06681-C06-01 TIN2010-1505

A systematic review of data quality issues in knowledge discovery tasks

Hay un gran crecimiento en el volumen de datos porque las organizaciones capturan permanentemente la cantidad colectiva de datos para lograr un mejor proceso de toma de decisiones. El desafío mas fundamental es la exploración de los grandes volúmenes de datos y la extracción de conocimiento útil para futuras acciones por medio de tareas para el descubrimiento del conocimiento; sin embargo, muchos datos presentan mala calidad. Presentamos una revisión sistemática de los asuntos de calidad de datos en las áreas del descubrimiento de conocimiento y un estudio de caso aplicado a la enfermedad agrícola conocida como la roya del café.Large volume of data is growing because the organizations are continuously capturing the collective amount of data for better decision-making process. The most fundamental challenge is to explore the large volumes of data and extract useful knowledge for future actions through knowledge discovery tasks, nevertheless many data has poor quality. We presented a systematic review of the data quality issues in knowledge discovery tasks and a case study applied to agricultural disease named coffee rust

Fuzzy investment decision support for brownfield redevelopment

Tato disertační práce se zaměřuje na problematiku investování a podporu rozhodování pomocí moderních metod. Zejména pokud jde o analýzu, hodnocení a výběr tzv. brownfieldů pro jejich redevelopment (revitalizaci). Cílem této práce je navrhnout univerzální metodu, která usnadní rozhodovací proces. Proces rozhodování je v praxi komplikován též velkým počet relevantních parametrů ovlivňujících konečné rozhodnutí. Navržená metoda je založena na využití fuzzy logiky, modelování, statistické analýzy, shlukové analýzy, teorie grafů a na sofistikovaných metodách sběru a zpracování informací. Nová metoda umožňuje zefektivnit proces analýzy a porovnávání alternativních investic a přesněji zpracovat velký objem informací. Ve výsledku tak bude zmenšen počet prvků množiny nejvhodnějších alternativních investic na základě hierarchie parametrů stanovených investorem.This dissertation focuses on decision making, investing and brownfield redevelopment. Especially on the analysis, evaluation and selection of previously used real estates suitable for commercial use. The objective of this dissertation is to design a method that facilitates the decision making process with many possible alternatives and large number of relevant parameters influencing the decision. The proposed method is based on the use of fuzzy logic, modeling, statistic analysis, cluster analysis, graph theory and sophisticated methods of information collection and processing. New method allows decision makers to process much larger amount of information and evaluate possible investment alternatives efficiently.