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In this paper, we consider the problem of aggregating a collection of transitive fuzzy binary relations in such a way that the aggregation process preserves transitivity. Specifically, we focus our efforts on the characterization of those functions that aggregate a collection of fuzzy binary relations which are transitive with respect to a collection of t-norms preserving the transitivity. We characterize them in terms of triangular triplets. Further, the relationship between triangular triplets, the monotonicity of the aggregation function and an appropriate dominance notion is explicitly stated. Special attention is paid to a few classes of transitive fuzzy binary relations that are relevant in the literature. Concretely, we describe, in terms of triangular triplets, those functions that aggregate a collection of fuzzy pre-orders, fuzzy partial orders, relaxed indistinguishability relations, indistinguishability relations and equalities. A surprising relationship between functions that aggregate transitive fuzzy relations into a T M -transitive fuzzy relation and those that aggregate relaxed indistinguishability relations is shown. A few consequences of the new results are also provided for those cases in which all the t-norms of the given collection are the same. Some celebrated results are retrieved as a particular case from the exposed theory.

The study of consistency in decision-making models is of great importance. Our proposal deals with a special type of extended aggregation functions to guarantee consistency that is based on T-S consistency of linearly ordered fuzzy preference relations (fuzzy ranking for preferences). Necessary conditions to ensure consistency in the aggregation process are provided. Moreover, sufficient conditions to guarantee the existence of extended aggregation functions verifying T-S consistency are presented. Some examples of functions of this type are also given. The equivalence between T-S consistency and the additive consistency for fuzzy preference relations is established.

Background Despite the extensive scientific evidence accumulating on the epidemiological risk factors for non-alcoholic fatty liver disease (NAFLD), evidence exploring sex- and age-related differences remains insufficient. The present cross-sectional study aims to investigate possible sex differences in the prevalence of FLI-defined NAFLD as well as in its association with common risk factors across different age groups, in a large sample of Spanish working adults. Methods This cross-sectional study included data from 33,216 Spanish adult workers (18–65 years) randomly selected during voluntary routine occupational medical examinations. Sociodemographic characteristics (age and social class), anthropometric (height, weight, and waist circumference) and clinical parameters (blood pressure and serum parameters) were collected. NAFLD was determined by the validated fatty liver index (FLI) with a cut-off value of ≥ 60. The presence of metabolic syndrome (MetS) was assessed according to the diagnostic criteria of the International Diabetes Federation. Cardiovascular risk was determined using the REGICOR-Framingham equation. The association between FLI-defined NAFLD and risk factors by sex and age was evaluated by multivariate logistic regression. Results The prevalence of FLI-defined NAFLD (FLI ≥ 60) was 19.1% overall, 27.9% (95% CI 23.3–28.5%) for men and 6.8% (95% CI 6.4–7.3%) for women and increasing across age intervals. As compared to women, men presented worse cardiometabolic and anthropometric profiles. The multivariate analysis model showed that hepatic steatosis assessed by FLI was strongly associated with age, HDL-cholesterol, social class, prediabetes, diabetes, prehypertension, hypertension, and smoking status for both men and women. The association between diabetes and hypertension with FLI-defined NAFLD was stronger in women than in men at both univariate and multivariate analyses. Conclusions Men presented a higher prevalence of NAFLD than women across all age intervals, as well as a worse cardiometabolic profile and a higher cardiovascular risk. Nevertheless, the association between FLI-defined NAFLD and diabetes or hypertension was significantly stronger in women than in men, possibly indicating that the presence of a dysmetabolic state might affect women more than men with regard to liver outcomes.

In many fields of applied sciences, the aggregation of numerical values, in order to get a final one which allows to make a decision, plays a central role. Many times these numerical values represe...

In this contribution we address our attention on the aggregation of partial T-indistinguishability operators (relations) and partial pseudo-metrics. A characterization of those functions that allow to merge a collection of partial T–indistinguishability operators into a new one was provided by Calvo et al. in [10] by means of ( T , T M ) -tuples, but here we present another characterization in terms of ( + , max ⁡ ) -tuples. Also, we analyze the aggregation of a collection ( E i ) i = 1 n of partial T i -indistinguishability operators. Moreover, we provide that a generalized inter–exchange composition functions condition is a sufficient condition to guarantee that a function merges partial T i -indistinguishability operators into a single one. In addition, we give different expressions of those aggregation functions that are object of our study, most of them are defined by means of the additive generators of the corresponding t-norms and another particular function. We see that the functions, that merge partial S-pseudo-metrics into a new one, are related to the functions that aggregate partial pseudo-metrics. Finally, we show the relation between the functions, that merge partial T-indistinguishability operators and the functions that preserve the partial T ⁎ -pseudo-metrics in the aggregation process.

We propose a new type of weighted averaging functions given implicitly as a solution to an algebraic equation. The main ingredient is incorporation of weights performed by using a function different to the product. Strict triangular norms are one example of such functions. We show that the weights should be normalized in this case differently to the usual sum to one condition. We establish the conditions under which the implicit averages are well defined, are idempotent, monotone and bounded by the minimum and maximum of their arguments. We present many examples of implicit averages, some of which recover the existing families of functions while others define new families. In particular we provide new generalizations of power means, density based averages and weighted OWA functions.

An emotion communication system based on linearly ordered fuzzy preferences is proposed, whose objective is to determine the appropriate actions on the environment in order to enhance user comfort. Once a subset of elementary preferences is obtained via basic human-machine interactions, the rest of preference relations are determined in such a way that the consistency of the system is guaranteed. For this purpose, the Łukasiewicz t-conorm is applied as a rule for aggregation.

In 1982, E. Trillas introduced the notion of indistinguishability operator with the main aim of fuzzifying the crisp notion of equivalence relation. In the study of such a class of operators, an outstanding property must be stressed. Concretely, there exists a duality relationship between indistinguishability operators and metrics. The aforesaid relationship was deeply studied by several authors that introduced a few techniques to generate metrics from indistinguishability operators and vice-versa. In the last years a new generalization of the metric notion has been introduced in the literature with the purpose of developing mathematical tools for quantitative models in Computer Science and Artificial Intelligence. The aforesaid generalized metrics are known as relaxed metrics. The main purpose of the present paper is to explore the possibility of making explicit a duality relationship between indistinguishability operators and relaxed metrics in such a way that the aforementioned classical techniques to generate both concepts, one from the other, can be extended to the new framework., This is a preprint version of the paper available from https://link.springer.com/article/10.1007/s00500-018-03675-9. This work is also supported by project PGC2018-095709-B-C21 (MCIU/AEI/FEDER, UE), and PROCOE/4/2017 (Govern Balear, 50% P.O. FEDER 2014-2020 Illes Balears).

The problem of the consistency of qualitative judgements about the difference of attractiveness between alternatives is studied. Our proposal deals with smooth t-conorms to be used for aggregation of elementary judgements.

HighlightsAn epidemiologic system analysis of cardiovascular risk is presented through a Bayesian network model.The Bayesian network model can serve as a generic tool for application oriented activities: explanation, prediction, monitoring and prevention.Due to cardiovascular disease is multifactorial, the application of this kind of model is of special interest, both from theoretical and practical point of view.The induced Bayesian network was used to make inferences taking into account three reasoning patterns: causal reasoning, evidential reasoning, and intercausal reasoning. An extensive, in-depth study of cardiovascular risk factors (CVRF) seems to be of crucial importance in the research of cardiovascular disease (CVD) in order to prevent (or reduce) the chance of developing or dying from CVD. The main focus of data analysis is on the use of models able to discover and understand the relationships between different CVRF. In this paper a report on applying Bayesian network (BN) modeling to discover the relationships among thirteen relevant epidemiological features of heart age domain in order to analyze cardiovascular lost years (CVLY), cardiovascular risk score (CVRS), and metabolic syndrome (MetS) is presented. Furthermore, the induced BN was used to make inference taking into account three reasoning patterns: causal reasoning, evidential reasoning, and intercausal reasoning. Application of BN tools has led to discovery of several direct and indirect relationships between different CVRF. The BN analysis showed several interesting results, among them: CVLY was highly influenced by smoking being the group of men the one with highest risk in CVLY; MetS was highly influence by physical activity (PA) being again the group of men the one with highest risk in MetS, and smoking did not show any influence. BNs produce an intuitive, transparent, graphical representation of the relationships between different CVRF. The ability of BNs to predict new scenarios when hypothetical information is introduced makes BN modeling an Artificial Intelligence (AI) tool of special interest in epidemiological studies. As CVD is multifactorial the use of BNs seems to be an adequate modeling tool.

The purpose of this paper was to discover the relationships among 22 relevant psychological features in semi-professional football players in order to study team’s performance and collective efficacy via a Bayesian network (BN). The paper includes optimization of team’s performance and collective efficacy using intercausal reasoning pattern which constitutes a very common pattern in human reasoning. The BN is used to make inferences regarding our problem, and therefore we obtain some conclusions; among them: maximizing the team’s performance causes a decrease in collective efficacy and when team’s performance achieves the minimum value it causes an increase in moderate/high values of collective efficacy. Similarly, we may reason optimizing team collective efficacy instead. It also allows us to determine the features that have the strongest influence on performance and which on collective efficacy. From the BN two different coaching styles were differentiated taking into account the local Markov property: training leadership and autocratic leadership.

In this paper we focus our attention on exploring the aggregation of partial T-indistinguishability operators (relations). Concretely we characterize, by means of (T-\(T_{\min }\))-tuples, those functions that allow to merge a collection of partial T-indistinguishability operators into a single one. Moreover, we show that monotony is a necessary condition to ensure that a function aggregates partial T-indistinguishability operators into a new one. We also provide that an inter-exchange composition function condition is a sufficient condition to guarantee that a function aggregates partial T-indistinguishability operators. Finally, examples of this type of functions are also given.

The purpose of this paper is the study of relationships between negative psychological features in young competitive team players via a Bayesian network (BN). The BN let us describe in graphical terms the dependencies and conditional independencies between variables in a multivariate context, and therefore it let us analyze the relationships between the type of motivational climate and orientation of team players (from two different frameworks: goal orientation theory, and self-determination motivation theory), and we took into account their willingness to accept the use of gamesmanship and cheating at the games, related with somatic and cognitive pre-competitive anxiety. The BN analysis includes three reasoning patterns: evidential reasoning, causal reasoning and intercausal reasoning. We built a BN from a data set composed of twelve psychological variables, which were identified as relevant to this study. The structure and parameters were learnt with TETRAD IV and the BN was implemented in Netica software.

Recently knowledge has been obtained about the Cooperative meta-dynamics in performance teams, and also on the fit between the manager’s and team member’s beliefs about teamwork and performance. To obtain this, a specific instrument has been created and validated, the Questionnaire on Cooperation in Performance Teams (CWQ). The need for such this kind of tool is double fold: first, to combine the most relevant conceptual theories in a short and friendly usable instrument, and to obtain easily applicable knowledge addressed to managers and coaches working with performance teams. In order to accomplish fully with this aim, a confirmatory analysis of the new instrument is required too. Consequently, the CWQ was administered to 218 players of performance sports teams (Mean age = 21.12; SD = 6.72; mean years of experience = 11.42; SD = 6.33). The data analysis consisted on the study of the main components (forcing and without forcing the number of factors), with a Varimax rotation. The results confirm the validation of the CWQ both for the “A” and “B” versions of the questionnaire and the existence of four meta-factors: 1. Global cooperation with the team; 2. Cooperation for personal growth in the team; 3. Emotional cooperation, and 4. Conditional cooperation. The four factors shown factorial weights similar to those obtained in the previous exploratory study. These data confirms its transcultural and transituational invariance of the CWQ, as along with its conceptual validity and the solid theoretical conception of the abovementioned factors, and also its applicability in various performance environments. In addition, a mathematical analysis has been introduced to evaluate the symmetry between cooperative work beliefs from both coach and player views, embedded in the conceptual framework of the Cognitive Dissonance Theory.

This paper addresses one of the main problems to solve in a multi-robot system, allocating tasks to a set of robots (multi-robot task allocation-MRTA). Among all the approaches proposed in the literature to face up MRTA problem, this paper is focused on swarm-like methods called response threshold algorithms. The task allocation algorithms inspired on response threshold are based on probabilistic Markov chains. In the MRTA problem literature, possibilistic Markov chains have proved to outperform the probabilistic Markov chains when a Max-Min algebra is considered for matrix composition. In this paper we analyze the system behavior when a more general algebra than the Max-Min one is taken for matrix composition. Concretely, we consider the algebra \(([0,1], S_{M},T)\), where \(S_{M}\) denotes the maximum t-conorm and T stands for any t-norm. The performed experiments show how only some well-known t-norms are suitable to allocate tasks and how the possibility transition function parameters are related to the used t-norm.

In this study, we try to discover the natural psychological dynamics in a cooperative work team. We have selected a group of individuals that can help us to explore the psychological processes when working in a team. A new tool is used which has been developed from the most relevant conceptual frameworks existing at the moment, the Cooperative Workteams Questionnaire, (CWQ). In this paper, we present the psychometric characteristics and impact encountered by the conceptual framework. We also present an analysis of the results obtained from applying this framework.

In 1981, J. Borsik and J. Dobos studied the problem of how to merge, by means of a function, a family of distances into a single one. To this end, they introduced the notion of distance aggregation function and gave a characterization of such functions. Later on, in 2010, the notion of distance aggregation function was extended to the framework of asymmetric distances by G. Mayor and O. Valero. Thus, asymmetric distance aggregation functions were introduced and a characterization of this new type of functions was also given. Concretely, the aforesaid characterization states that the functions which allow to merge a family of asymmetric distances into a single one are exactly those that are amenable, monotone and subadditive. In the present chapter we consider the problem of aggregating a family of bounded asymmetric distances. To this end, the notion of bounded asymmetric distance aggregation function is introduced and a full description of such functions is provided. The obtained results are illustrated by means of examples. Furthermore, the relationship between asymmetric aggregation functions and the bounded ones is discussed.

In this work, a new lattice L determined by the class of weighting triangles as a base of L-fuzzy subsets is proposed. Furthermore, extended orders and operators which are obtained by means of fuzzy binary relations \(F_{\triangle }\) associated to a weighting triangle are included. Moreover, some new expressions have been defined for Extended Ordered Weighted Averaging operators, and Extended Aggregation functions.

Title: A Bayesian Analysis of the motivation, motivational climate and anx- iety in young competitive team players. Abstract: The aim of this study is to analyze the relationship between the self-determinated motivation, the goal orientation and the perceived moti- vational climate and their impact on the cognitive and somatic components of the competitive anxiety in young athletes, and their acceptance of the use of cheating and gamemanship in sport. We administered PMCSQ, TEOSQ, BRSQ, CDED and SAS- 2 to 270 football, handball and basket- ball players (Mean age = 14.67, SD = 1.53). Probabilistic relationships of dependence and independence of the variables were studied by a Bayesian network (BN), developed using Netica and Tetrad IV. After the validation of the BN, we instantiated hypothetical probability values of several de- pendent variables in order to analyze the variation of the probability of the independent variables. Results show different statistical dependence rela- tionships between the self-determined motivation and achievement moti- vation, respect to the competitive anxiety, and also show a controversial re- lationship between the perceived motivational climate and the task and ego orientation of the players. It also shows the residual role of the somatic anxiety, and the instrumental role of the the use of cheating and ga- memanship.

The purpose of this study was to discover the relationships among 18 psychological features in a cooperative team in order to analyse work team performance. A Bayesian network (BN) has been built from a dataset of 403 soccer semi-professional players, taking into account prototypical sportive teams with respect to other workteams, regarding its psychological features, such as leadership, cohesion or group roles. The BN shows three conditionally independent features according to the local Markov property: two cohesion dimensions and the cooperative style of management/coaching; and features such as players satisfaction, experience, social integration in the team, and the workplace specificity, i.e., the players’ positions, which were located at the bottom in the BN show a clear dependence. The BN was used to make inferences achieving: (1) The social side of the cohesion has a low likelihood influence on the performance; (2) All psychological leadership styles (positive and/or negative) have some influence on the performance, the years remaining in the same team, and the player’s position; (3) The positive leadership style is not a required condition for the performance or for the player’s satisfaction, but a consequence of the other psychological variables.