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

Session: Fuzziness

16 articles
Proceedings Article

Lower Approximations by Fuzzy Consequence Operators

Jorge Elorza, Jordi Recasens
Three ways to find lower approximations of a given fuzzy operator are given. A Representation Theorem for fuzzy consequence operators is obtained.
Proceedings Article

Study of the choice of the weighting measure φ on the φ-wabl/ldev/rdev median

Beatriz Sinova, María Teresa López
When summarizing the location of a random fuzzy number, some more robust approaches than the well-known Aumann-type mean have been proposed in the literature. Among them, the φ-wabl/ldev/rdev median extends the concept of median from the real-valued case. The characterization for fuzzy numbers and...
Proceedings Article

Towards objective Bayesian foundations with fuzzy events

Pedro Terán
We present an axiomatic approach to conditional measures of fuzzy events which is inspired by the Dupré–Tipler argument for Bayesianism. Unlike there or in the older and related Cox argument, although we are able to derive additive probabilities other non-additive solutions exist. Our motivation is to...
Proceedings Article

WOWA operators in fuzzy context sequences

Cristina Alcalde, Ana Burusco
In some cases, the relationship between an object set X and an attribute set Y is set up by means of a fuzzy context sequence. A particular case of this situation appears when we want to study the evolution in time of a fuzzy context. In this work, we deepen in the study of these situations. First we...
Proceedings Article

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...
Proceedings Article

Fuzzy Covering based Rough Sets Revisited

Lynn D’eer, Chris Cornelis, Daniel Sánchez
In this paper we review four fuzzy extensions of the socalled tight pair of covering based rough set approximation operators. Furthermore, we propose two new extensions of the tight pair: for the first model, we apply the technique of representation by levels to define the approximation operators, while...
Proceedings Article

Logic of prototypes and counterexamples: possibilities and limits

Thomas Vetterlein
Fuzzy sets are a popular tool to model vague properties. It is, however, well-known that this model usually involves a good degree of arbitrariness. In this contribution we consider the possibility of standardising the construction of fuzzy sets at least withregard to the borderline cases. To this end,...
Proceedings Article

On Strongly Standard Complete Fuzzy Logics: MTLQ* and its Expansions.

Amanda Vidal, Lluis Godo, Francesc Esteva
Finding strongly standard complete axiomatizations for t-norm based fuzzy logics (i.e. complete for deductions with infinite sets of premises w.r.t. semantics on the real unit interval [0, 1]) is still an open problem in general, even though results are already available for some particular cases like...
Proceedings Article

Similarity based one-sided tests for the expected value and interval data

Przemyslaw Grzegorzewski, Ana Belén Ramos-Guajardo
A novel way for addressing one-sided hypothesis tests for the mean of unable to observe real random variables from which we have information provided in terms of interval data is proposed. For this purpose, a measure of similarity between intervals is considered and the classical one-sided hypothesis...
Proceedings Article

Towards a fuzzy-linguistic based social network sentiment-expression system

Valerio Perticone, Francesco D’Aleo, Giovanni Rizzo, Marco Elio Tabacchi
Liking allows users of Social Networks, blogs and online magazines to express their support of posts and artifacts by a simple click. Such function is very popular but lacks semantic power, and some platforms have augmented it by allowing to choose a pictographic depiction corresponding to a feeling....
Proceedings Article

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...
Proceedings Article

δ-information reducts and bireducts

Mª José Benítez, Jesús Medina, Dominik Slezak
Attribute reduction is an important step in order to decrease the computational complexity to derive information from databases. In this paper, we extend the notions of reducts and bireducts introduced in rough set theory for attribute reduction purposes and let them work with similarity relations defined...
Proceedings Article

Fuzziness, Cognition and Cybernetics: a historical perspective

Rudolf Seising, Marco Elio Tabacchi, Settimo Termini, Enric Trillas
In the present paper, we connect some old reflections about the relationships existing between the theory of fuzzy sets and cybernetics with modern, contemporary analyses of the crucial (better: unavoidable) role that fuzziness plays in the attempts at scientifically describing aspects of information...
Proceedings Article

Fuzziness, Cognition and Cybernetics: an outlook on future

Enric Trillas, Settimo Termini, Marco Elio Tabacchi, Rudolf Seising
In the present paper, we connect some old reflections about the relationships existing between the theory of fuzzy sets and cybernetics with modern, contemporary analyses of the crucial (better: unavoidable) role that fuzziness plays in the attempts at scientifically describing aspects of information...
Proceedings Article

A perspective on the extension of stochastic orderings to fuzzy random variables

Inés Couso, Didier Dubois
In this paper we study how to make joint extensions of stochastic orderings and interval orderings so as to extend methods for comparing random variables, from the point of view of their respective location or magnitude, to fuzzy random variables. The main idea is that the way fuzzy random variables...
Proceedings Article

Combination of measurement uncertainty contributions via the generalized Dombi operator

Alessandro Ferrero, Marco Prioli, Simona Salicone, Wei Jiang
Possibility is considered as a promising mathematical tool to represent that particular case of incomplete information given by a measurement result. A measurement result can be affected by systematic and random effects. The combination of random contributions in the possibility theory returns only approximated...