Proceedings of the 2015 Conference of the International Fuzzy Systems Association and the European Society for Fuzzy Logic and Technology

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236 articles

Examples of Aggregation Operators on Membership Degrees of Type-2 Fuzzy Sets

Susana Cubillo, Pablo Hernández, Carmen Torres-Blanc
Z. Taká c in [16] introduced the aggregation operators on any subalgebra of M (set of all fuzzy membership degrees of the type-2 fuzzy sets, that is, the functions from [0,1] to [0,1]). Furthermore, he applied the Zadeh’s extension principle (see [24]) to obtain in [16, 17] a set of aggregation operators...

Measuring dependence between dimensions of poverty in Spain: An approach based on copulas

Ana Pérez, Mercedes Prieto
Welfare and close related issues, like poverty and ine-quality, are multidimensional as they involve not only income, but also education, health or labour. This paper aims to measure the dependence among dimensions us-ing copula-based coefficients. This approach focuses on the positions of the individuals...

Generalised Fuzzy Bayesian Network with Adaptive Vectorial Centroid

Ku Muhammad Naim Ku Khalif, Alexander Gegov
In this paper, the theoretical foundations of generalised fuzzy Bayesian Network based on Vectorial Centroid defuzzification is introduced. The extension of Bayesi-an Network takes a broad view by examples labelled by a fuzzy set of attributes, instead of a classical set. Com-bining fuzzy set theory...

GASRP-FP: A hybrid metaheuristic to solve fuzzy portfolio selection with non-financial goals

José Manuel Cadenas, Mª Carmen Garrido, Raquel Martínez, Clara Calvo, Carlos Ivorra, Vicente Liern
The emergence of more powerful computational techniques has stimulated the development and study of more sophisticated models for portfolio selection problem including further constraints and further financial and non-financial decision criteria. In this paper, we propose a hybrid approach composed of...

Information retrieval from interval-valued fuzzy automata through K operators

Inmaculada Lizasoain, Marisol Gómez, Cristina Moreno
Here we study the notions of lattice-valued finite state machine and lattice-valued fuzzy transformation semigroup when the lattice consists of all the closed subintervals contained in [0, 1]. So, we can apply techniques of interval-valued fuzzy sets to fuzzy automata. In particular, we prove that Atanassov’s...

Improving medical decisions under incomplete data using interval–valued fuzzy aggregation

Patryk Zywica, Andrzej Wójtowicz, Anna Stachowiak, Krzysztof Dyczkowski
We state a problem concerning how to make an effective and proper decision in the presence of data incompleteness. As an example we consider a medical diagnostic system where the problem of missing data is commonly encountered. We propose and evaluate an approach that makes it possible to reduce the...

Intuition based Decision Methodology for Ranking Interval Type – II Fuzzy Numbers

Ahmad Syafadhli Abu Bakar, Alexander Gegov
Type – II fuzzy number is introduced in decision mak-ing analysis as a concept that is capable to effectively deal with uncertainty in the information about a deci-sion. As type – II fuzzy number is represented by possi-bility distribution, it is hard to determine which type – II fuzzy number is greater...

A Bipartite Graph Based Competitiveness Degrees Analysis with Query Logs on Search Engine

Dandan Qiao, Qiang Wei, Jin Zhang, Guoqing Chen
Competitive intelligence analysis based on user gener-ated contents (UGCs) shows advantages on possessing the benefit of the wisdom of crowds, evading cognitive biases and timely updating. This paper investigates and constructs a bipartite graph model by extracting joint co-occurrence of competitors...

Evidential likelihood flatness as a way tomeasure data quality: the multinomial case

Liyao Ma, Sébastien Destercke, Yong Wang
Likelihood functions, as well as the more recent concept of evidential likelihood, are essential statistical tools to perform estimation. Beyond the maximal likelihood value, the shape of the likelihood can also give interesting information about the data used to get the estimation. Indeed, it is generally...

On Perception-based Logical Deduction and Its Variants

Martin Stepnicka, Antonín Dvorák
We present and analyze inference method called Perception-based Logical Deduction (PbLD) aimed at the treatment of fuzzy IF-THEN rules as linguistically expressed genuine logical implications. Besides the original PbLD, we propose a new balancing variant of PbLD, introduce both variants with fuzzy inputs...

Method for the minimum cost maximum flow determining in fuzzy dynamic network with nonzero flow bounds

Alexander Bozhenyuk, Evgeniya Gerasimenko, Igor Rozenberg, Irina Perfilieva
In this paper the method for the minimum cost flow determining in fuzzy dynamic network with nonzero lower flow bounds is proposed. Considered method takes into account fuzzy nature of networks’ parameters and deals with fuzzy arc flow bounds, fuzzy transmission costs. Fuzzy arc flow bounds, costs and...

Modulo similarity in comparing histograms

Pasi Luukka, Mikael Collan
Histograms are a tool for graphical representation of frequency data and thus helpful in creating a fast understanding of, e.g., contents of frequency data. Comparing histograms is topic of increasing importance due to an increase in the availability of data sets containing frequency information. Automatic...

Optimization of the ordinal and cardinal consistency of a preference matrix in decision making

Martin Gavalec, Karel Mls, Hana Tomášková
In multi-criteria decision problems the relative importance of alternatives is computed from preference matrices, which come from experience and can possibly be inconsistent. Two consistency types of preferences are studied in the paper. The ordinal consistency preserves the order in which the alternatives...

A general fuzzy set representation for decision making

Luca Anzilli, Gisella Facchinetti
In this paper we propose a general procedure to represent a fuzzy set that may be non-normal and/or non-convex. This representation will be offered by an interval and a crisp value. This idea is useful either in optimization and decision making problems or in defuzzification step of a fuzzy inference...

An analysis of the median of a fuzzy random variable based on Zadeh’s extension principle

Sonia Pérez-Fernández, Beatriz Sinova
The median of a fuzzy random variable has been extended either by applying Zadeh’s extension principle or by minimizing its mean distance w.r.t. a fuzzy number when a certain L1 metric is considered. This paper aims to analyze connections between both approaches along with some properties of the first...

Worldwide Investing in Real Estate Using Interval-Valued Intuitionistic Fuzzy Sets

Irem Otay, Cengiz Kahraman
Global real estate investments have been one of the popular investment areas since developments in trans-portation vehicles among countries, significant reduc-tion in travelling costs, and suitable legal arrangements for purchasing real estates in a foreign country have made it attractive. This investment...

Evolutionary Optimization of complex Systems in Uncertain Environments

Yaochu Jin
This talk aims to discuss the main challenges in evolutionary optimization of complex systems to bridge the gap between the academic research and the urgent demands from industry. We will show that, while solving “hard” problems, such as multi-modal and strongly correlated problems, multi-objective optimization...

Fuzzy Sets, Cut Systems and Closure Operators in Sets with Similarities

Jirí Mockor
Closure operators defined on various sets (set of all classical fuzzy sets, set of all semi-cuts, set of all cuts in a Q-set, etc.) are investigated and it is shown how a closure operator defined on one set can be extended to a closure operator defined on another set.

Fuzzy relational equations and the covering problem

Qing-quan Xiong, Qian-yu Shu
The work considers the problem of solving a system of fuzzy relational equations with inf-implication composition and introduces the concepts of a characteristic matrix and attainable components. It is first shown that solving the system is closely related with the covering problem. Further, it is proved...

Steady states of max-Lukasiewicz fuzzy systems

Zuzana Nemcová
The paper gives the systematic characterization of eigenspace in max-T algebra where T is equal to ukasiewicz t-norm. Max- ukasiewicz fuzzy algebra can be used for the description of the states of Discrete-event systems. The states can represent a balance of the resource unit expended during the evolution...

Investor’s satisfaction in portfolio selection problem

Aleksandra Rutkowska
Empirical studies show that individual investors do not always behave rationally and do not use standard investment portfolio selection tasks. In this paper we focus on investor choices and the basic elements affecting them. The paper presents optimization model based on a measure of investor satisfaction....

Residual implications derived from uninorms satisfying Modus Ponens

Margarita Mas, Miquel Monserrat, Daniel Ruiz-Aguilera, Joan Torrens
Modus Ponens is a key property for fuzzy implication functions that are going to be used in fuzzy inference processes. In this paper it is investigated when fuzzy implication functions derived from uninorms via residuation, usually called RUimplications, satisfy the modus ponens with respect to a continuous...

The role of Precise and Imprecise Syllogisms in the di-agnosis of reasoning deficits in mental disorders

Alejandro Sobrino, Martín Pereira-Fariña
In this paper we will inquiry about the role of precise and imprecise syllogisms for diagnosing reasoning im-pairments in people suffering some mental disorders. Additionally, we propose some new questions that can help to better understand the already studied deficits and, perhaps, to progress in the...

Optimum allocation of centers in fuzzy transportation networks with the largest vitality degree

Vitalii Bozheniuk, Alexander Bozhenyuk, Stanislav Belyakov
Fuzzy graph, fuzzy directed way, accessible degree, fuzzy transitive closure, reachability degree, strong connection degree, vitality degree, fuzzy set of vitality.

Measuring Quality Policy Deployment: A Fuzzy Logic Approach

Juan Cogollo-Flórez, Myladis Cogollo-Flórez, Andrea Flórez-Rendón
Global and balanced performance measurement in Qual-ity Policy Deployment is a key element of quality man-agement in public Higher Education Institutions (HEI´s). This paper describes the design of a fuzzy linguistic model for measuring Quality Policy Deployment in a Colombian public HEI. The proposed...

Improving Pairwise Learning Classification in Fuzzy Rule Based Classification Systems Using Dynamic Classifier Selection

Alberto Fernández, Mikel Galar, José Antonio Sanz, Humberto Bustince, Francisco Herrera
classification based on the One-vs-One decomposition strategy has shown a high quality for addressing those problems with multiple classes, even if the learning model enables the discrimination among several concepts. The main phase of the pairwiselearning is the decision process, where the outputs of...

Infinitesimals and Pavelka logic

Esko Turunen, Mirko Navara
Rational Pavelka Logic does not admit infinitesimals. We argue that infinitesimals are important in logic and we present an alternative approach which admits them. It is built up in a similar style, but based on the Chang’s perfect MV-algebra. We prove a partial result towards the completeness of this...

A tentative fuzzy assessment of the quality of teaching and opportunities to learn mathematics in a classroom discussion

Itziar García-Honrado, Miquel Ferrer, Angela Blanco-Fernandez
We study classroom discussions to obtain a fuzzy summary of the quality of teaching and opportunities to learn mathematics created in whole-class settings. We consider the ten rubrics of the Instructional Quality Assessment and make a fuzzy interpretation of this tool. We selected two problems of proportionality...

Mining information from time series in the form of natural language expressions

Vilém Novák
In this paper, we discuss three tasks of mining information from time series, namely finding intervals with monotonous trend, evaluation of it in sentences of natural language, and summarizing information using intermediate quantifiers. The mined information is presented in simple sentences of natural...

Applying Two Different Methods to Extend Restricted Dissimilarity Functions

Eduardo Palmeira, Benjamín Bedregal, Humberto Bustince
Based on previous investigations, we have proposed two different methods to extend lattice-valued fuzzy connectives (t-norms, t-conorms, negations and implications) and other related operators, considering a generalized notion of sublattices. Taking into account the obtained results that we have obtained...

On Intuitionistic Fuzzy Metric Neighbourhoods

Evgeniy Marinov, Peter Vassilev, Krassimir Atanassov
The concept of an intuitionistic fuzzy neighbourhood is introduced. This notion turns out to be more sensitive to variations in the different points of the universe compared to the standard neighbourhood definition of metric space. We apply the intuitionistic fuzzy neighbourhood to the extended modal...

Autoassociative Fuzzy Implicative Memory on the Platform of Fuzzy Preorder

Irina Perfilieva, Marek Vajgl
We propose a new theoretical justification of implicative fuzzy associative memory. It is based on the notion of a fuzzy preorder operator. Moreover, we give a necessary and sufficient condition on input data that guarantees insensitivity to a certain type of noise. The latter is precisely characterized....

A new optimization approach for indoor location based on Differential Evolution

Antonio D. Masegosa, Alfonso Bahillo, Enrique Onieva, Pedro López-García, Asier Perallos
The growth of Location Based Services and Location Aware Services in indoor environments has focused the attention of the research community on indoor location systems, especially on those based on WLAN networks and Received Signal Strength (RSS). Despite the advances reached, the development of reliable,...

Participatory Learning in Linked Open Data

Marek Z. Reformat, Ronald R. Yager
The introduction of Resource Description Framework (RDF) as a fundamental data representation format of Semantic Web is changing a way how data is stored on the Internet. The intrinsic features of RDF data, i.e., its interconnections and simplicity of expressing information as triples: two entities connected...

Stabilization for the T–S fuzzy system with the constrained control

Chung-Hsun Sun, Wen-June Wang
In this study, the stabilization for the Takagi-Sugeno (T-S) fuzzy discrete system with constrained controls is investigated. The derived stabilization conditions are based on the Lyapunov stability criterion with the piecewise quadratic Lyapunov function. The constrained control inputs are used to assess...

A proposal for regime change/duration classification in chaotic systems

Priscilla Lopes, Ivana Yoshie Sumida, Heloisa A. Camargo, Haroldo De Campos Velho, Sandra Sandri
In order to to predict regime duration in a given chaotic system, for a set of output prototypes are available, we propose to use a clustering technique for the definition of classes of regime duration, which are then used by a chosen classifier. In this way, the exact boundaries between classes are...

Iris recognition with 4 or 5 fuzzy sets

Nicolaie Popescu-Bodorin, Cristina M. Noaica, Patricia Penariu
In current literature, the degrading performances of iris recognition systems is put in user’s responsibility (Biometric Menagerie-BM), or explained through a va-gue mix of time-related changes in biometric pattern, its presentation and the acquisition sensor (Template Age-ing-TA). Actually, BM and TA...

On interval pseudo-homogeneous uninorms

Lucelia Lima Costa, Benjamin Bedregal, Humberto Bustince, Marcus Rocha
In this paper, we introduce the concept of interval pseudo-homegeneous uninorms. We extend the concept of pseudo-homogeneity of specific functions for interval pseudo-homogeneous functions. It is studied two cases of interval pseudo-homogeneous uninorms, that is, interval pseudo-homogeneous tnorms and...

Fuzzy probability distribution with VaR constraint for portfolio selection

Marcus Rocha, Lucelia Lima, Helida Santos, Benjamin Bedregal
This work aims at comparing two models of fuzzy distribution: Normal and Laplace, whenever they are inside the context of possibilistic mean-variance model described by Li et al. in [ ], where fuzzy Normal distribution is used. We propose to make a comparison using their model, but instead we apply fuzzy...

Fuzzy Community detection based on grouping and overlapping functions

Daniel Gómez, J. Tinguaro Rodríguez, Javier Montero, Javier Yáñez
One of the main challenges of fuzzy community detection problems is to be able to measure the quality of a fuzzy partition. In this paper, we present an alternative way of measure the quality of a fuzzy community detection output based on n-dimensional grouping and overlapping functions that generalize...

An Approach to Interval Fuzzy Probabilities

Tiago Da Cruz Asmus, Graçaliz Pereira Dimuro, Benjamín Bedregal
Fuzzy sets and logic have been largely used for the treatment of the uncertainty, vagueness and ambiguity found in the modeling of real problems. However, there may exist also the case when there is uncertainty related to the membership functions to be used in the modeling of fuzzy sets and fuzzy numbers,...

A new class of fuzzy poverty measures

José Luis García-Lapresta, Casilda Laso de la Vega, Ricardo Alberto Marques Pereira, Ana Urrutia
In this paper, we introduce and analyze a class of fuzzy poverty measures based on exponential means. Since poverty is a vague notion, individuals should not be classified in poor or non-poor. In our proposal, we have associated a degree of poverty to each income through a fuzzy membership function....

On (OP)-polynomial implications

Sebastia Massanet, Juan Vicente Riera, Daniel Ruiz-Aguilera
The disposal of many families of fuzzy implications is crucial to handle the great number of applications these operators have. In this work, the class of fuzzy (OP)-polynomial implications is introduced as those fuzzy implications satisfying the ordering property (OP) whose expression in the region...

An axiomatic definition of cardinality for finite interval-valued hesitant fuzzy sets

Pelayo Quirós, Pedro Alonso, Irene Díaz, Vladimír Janiš
Recently, some extensions of the classical fuzzy sets are studied in depth due to the good properties that they present. Among them, in this paper finite interval-valued hesitant fuzzy sets are the central piece of the study, as they are a generalization of more usual sets, so the results obtained can...

Some properties of lattice OWA operators and their importance in image processing

Gustavo Ochoa, Inmaculada Lizasoain, Daniel Paternain, Humberto Bustince, Nikhil R Pal
In this work we deal with the problem of using OWA operators in color image reduction algorithms. For this reason, we study OWA operators defined on an arbitrary finite lattice endowed with a t-norm and a t-conorm. In the case of RGB color images, we apply OWA operators defined on a finite product lattice....

Lukasiewicz-like triangular subnorms

Milan Petrík, Peter Sarkoci
The paper defines and studies ukasiewicz-like triangular subnorms, i.e., triangular subnorms such that their level sets are obtained as unions of the level sets of the ukasiewicz triangular norm. As a result, the paper gives a characterization of these operations.

Interval-valued fuzzy clustering

Miguel Pagola, Aránzazu Jurio, Edurne Barrenechea, Javier Fernández, Humberto Bustince
In this work we propose an objective function to obtain an interval-valued fuzzy clustering. After the process of optimization we obtain an interval-valued fuzzy partition in which the length of the intervals depends on the position of the points with respect of the clusters.

On the relationship among F-transform, fuzzy rough set and fuzzy topology

Irina Perfilieva, Anand Pratap Singh, S.P. Tiwari
The objective of this work is to associate the concepts of fuzzy rough sets and fuzzy topologies with fuzzy transform. It is shown here that the fuzzy transform can be viewed as fuzzy approximation operators studied in the operator-oriented view of fuzzy rough set theory and the use of fuzzy rough set...

A hybrid forecast model combining fuzzy time series, linear regression and a new smoothing technique

Fábio José Justo dos Santos, Heloisa De Arruda Camargo
In recent years, Fuzzy Time Series have been considered a promising tool to deal with forecasting problems due to the ease to model the problems, the satisfactory results obtained and also to the low computational cost required. However, the long experience with traditional methods coming from statistics,...

N-contrapositivisation of fuzzy implication functions

Isabel Aguiló, Jaume Suñer, Joan Torrens
The law of contraposition with respect to a negation (usually strong) is one of the most studied properties in the theory of fuzzy implication functions. We already know some methods for modifying an implication with the aim that the new implication satisfies this property, these methods are called contrapositivisation....