8 research outputs found
Algorithms to Detect and Rectify Multiplicative and Ordinal Inconsistencies of Fuzzy Preference Relations
The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Consistency, multiplicative and ordinal, of fuzzy preference relations (FPRs) is investigated. The geometric consistency index (GCI) approximated thresholds are extended to measure the degree of consistency for an FPR. For inconsistent FPRs, two algorithms are devised (1) to find the multiplicative inconsistent elements, and (2) to detect the ordinal inconsistent elements. An integrated algorithm is proposed to improve simultaneously the ordinal and multiplicative consistencies. Some examples, comparative analysis, and simulation experiments are provided to demonstrate the effectiveness of the proposed methods
Consensus Reaching with Time Constraints and Minimum Adjustments in Group with Bounded Confidence Effects
The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.In the bounded confidence model it is widely known that individuals rely on the opinions of their close friends or people with similar interests. Meanwhile, the decision maker always hopes that the opinions of individuals can reach a consensus in a required time. Therefore, with this idea in mind, this paper develops a consensus reaching model with time constraints and minimum adjustments in a group with bounded confidence effects. In the proposed consensus approach, the minimum adjustments rule is used to modify the initial opinions of individuals with bounded confidence, which can further influence the opinion evolutions of individuals to reach a consensus in a required time. The properties of the model are studied, and detailed numerical examples and comparative simulation analysis are provided to justify its feasibility
A general multi-attribute multi-scale decision making method based on dynamic linmap for property perceived service quality evaluation
The scientific evaluation of property perceived service quality (PPSQ) needs multi-stage, multi-source and large-group perceived information, which is deemed to be the decision problem for dynamic, heterogeneous and large-scale data processing. Aiming at the problem, we propose a general multi-attribute multi-scale (MAMS) method based on the dynamic linear programming technique for multi-dimensional analysis of preference (LINMAP). In the dynamic LINMAP model, the classic MAMS matrix is introduced and extended into a general form. The dynamic LINMAP model is constructed by defining dynamic consistency and dynamic inconsistency. The time series weight is determined by Orness method. The new method adapts to the requirements of modern PPSQ. Finally, we verify the feasibility and effectiveness of dynamic LINMAP method by analyzing a PPSQ evaluation example. The new method improves the traditional PPSQ evaluation, and provides a perspective for large-scale data processing by the classic decision method.
First published online 23 June 202
Comparing aggregation methods in large-scale group AHP: time for the shift to distance-based aggregation
This paper aims to compare the efficiency of the conventional aggregation methods and the new, distance-based
aggregation techniques in simulated and real-world group AHP cases. For the comparison, we not only applied
rank correlation methods, but also examined the compatibility among the individual priority vectors of the group
and the created common priority vector in the different consensus creation approaches. Results have shown that
in small dimensions, both Euclidean Distance-Based Aggregation Method (EDBAM) and Aitchison Distance-Based
Aggregation Method (ADBAM) outperform significantly the conventional techniques. In large dimensions, the
dominance of EDBAM remains. Since the computational time of the proposed methods (especially EDBAM) is low
and EDBAM maintains its efficiency in large-scale group AHP (proven by 96.000 simulation cases) in every
possible dimension within the AHP domain, we can state in case of high number of evaluators, distance-based
aggregation is a better approach than the conventional methods
Managing consensus by multi-stage optimization models with linguistic preference orderings and double hierarchy linguistic preferences
Preference ordering structures are useful and popular tools to represent experts’ preferences in the decision making process. In the existing preference orderings, they lack the research on the precise relationship between any two adjacent alternatives in the preference orderings, and the decision making methods are unreasonable. To overcome these issues, this paper establishes a novel concept of linguistic preference ordering (LPO) in which the ordering of alternatives and the relationships between two adjacent alternatives should be fused well, and develops two transformation models to transform each LPO into the corresponding double hierarchy linguistic preference relation with complete consistency. Additionally, to fully respect the experts’ expression habits and provide more refined solutions to experts, this paper establishes a multi-stage consensus optimization model by considering the suggested preferences represented in both the continuous scale and the discrete scale, and develops a multi-stage interactive consensus reaching algorithm to deal with multi-expert decision making problem with LPOs. Furthermore, some numerical examples are presented to illustrate the developed methods and models. Finally, some comparative analyses between the proposed methods and models and some existing methods have been made to show the advantages of the proposed methods and models.
First published online 24 February 202
Argumentation dialogues in web-based GDSS: an approach using machine learning techniques
Tese de doutoramento em InformaticsA tomada de decisão está presente no dia a dia de qualquer pessoa, mesmo que muitas vezes ela
não tenha consciência disso. As decisões podem estar relacionadas com problemas quotidianos, ou
podem estar relacionadas com questões mais complexas, como é o caso das questões organizacionais.
Normalmente, no contexto organizacional, as decisões são tomadas em grupo.
Os Sistemas de Apoio à Decisão em Grupo têm sido estudados ao longo das últimas décadas com o
objetivo de melhorar o apoio prestado aos decisores nas mais diversas situações e/ou problemas a resolver.
Existem duas abordagens principais à implementação de Sistemas de Apoio à Decisão em Grupo:
a abordagem clássica, baseada na agregação matemática das preferências dos diferentes elementos do
grupo e as abordagens baseadas na negociação automática (e.g. Teoria dos Jogos, Argumentação, entre
outras).
Os atuais Sistemas de Apoio à Decisão em Grupo baseados em argumentação podem gerar uma
enorme quantidade de dados. O objetivo deste trabalho de investigação é estudar e desenvolver modelos
utilizando técnicas de aprendizagem automática para extrair conhecimento dos diálogos argumentativos
realizados pelos decisores, mais concretamente, pretende-se criar modelos para analisar, classificar e
processar esses dados, potencializando a geração de novo conhecimento que será utilizado tanto por
agentes inteligentes, como por decisiores reais. Promovendo desta forma a obtenção de consenso entre
os membros do grupo. Com base no estudo da literatura e nos desafios em aberto neste domínio,
formulou-se a seguinte hipótese de investigação - É possível usar técnicas de aprendizagem automática
para apoiar diálogos argumentativos em Sistemas de Apoio à Decisão em Grupo baseados na web.
No âmbito dos trabalhos desenvolvidos, foram aplicados algoritmos de classificação supervisionados
a um conjunto de dados contendo argumentos extraídos de debates online, criando um classificador
de frases argumentativas que pode classificar automaticamente (A favor/Contra) frases argumentativas
trocadas no contexto da tomada de decisão. Foi desenvolvido um modelo de clustering dinâmico para
organizar as conversas com base nos argumentos utilizados. Além disso, foi proposto um Sistema de
Apoio à Decisão em Grupo baseado na web que possibilita apoiar grupos de decisores independentemente
de sua localização geográfica. O sistema permite a criação de problemas multicritério e a configuração
das preferências, intenções e interesses de cada decisor. Este sistema de apoio à decisão baseado na
web inclui os dashboards de relatórios inteligentes que são gerados através dos resultados dos trabalhos
alcançados pelos modelos anteriores já referidos. A concretização de cada um dos objetivos permitiu
validar as questões de investigação identificadas e assim responder positivamente à hipótese definida.Decision-making is present in anyone’s daily life, even if they are often unaware of it. Decisions can be
related to everyday problems, or they can be related to more complex issues, such as organizational
issues. Normally, in the organizational context, decisions are made in groups.
Group Decision Support Systems have been studied over the past decades with the aim of improving
the support provided to decision-makers in the most diverse situations and/or problems to be solved.
There are two main approaches to implementing Group Decision Support Systems: the classical approach,
based on the mathematical aggregation of the preferences of the different elements of the group, and the
approaches based on automatic negotiation (e.g. Game Theory, Argumentation, among others).
Current argumentation-based Group Decision Support Systems can generate an enormous amount
of data. The objective of this research work is to study and develop models using automatic learning techniques
to extract knowledge from argumentative dialogues carried out by decision-makers, more specifically,
it is intended to create models to analyze, classify and process these data, enhancing the generation
of new knowledge that will be used both by intelligent agents and by real decision-makers. Promoting in
this way the achievement of consensus among the members of the group. Based on the literature study
and the open challenges in this domain, the following research hypothesis was formulated - It is possible
to use machine learning techniques to support argumentative dialogues in web-based Group Decision
Support Systems.
As part of the work developed, supervised classification algorithms were applied to a data set containing
arguments extracted from online debates, creating an argumentative sentence classifier that can
automatically classify (For/Against) argumentative sentences exchanged in the context of decision-making.
A dynamic clustering model was developed to organize conversations based on the arguments used. In
addition, a web-based Group Decision Support System was proposed that makes it possible to support
groups of decision-makers regardless of their geographic location. The system allows the creation of multicriteria
problems and the configuration of preferences, intentions, and interests of each decision-maker.
This web-based decision support system includes dashboards of intelligent reports that are generated
through the results of the work achieved by the previous models already mentioned. The achievement of
each objective allowed validation of the identified research questions and thus responded positively to the
defined hypothesis.I also thank to Fundação para a Ciência e a Tecnologia, for the Ph.D. grant funding with the reference: SFRH/BD/137150/2018