Jornadas de Seguimiento de Proyectos, 2009 Programa Nacional de Tecnologı́as Informáticas Representation, aggregation and classification models for decision making aiding under imprecise information TIN2006-06190 Javier Montero ∗ Faculty of Mathematics Complutense University of Madrid Abstract This project represents an evolution within a consolidated research group, which has been granted from the Spanish Programme for the Promotion of General Knowledge since 1988. The project is based on past results obtained in the framework of previous projects. The main core of this project is to study different components of decision aid tools under different kinds of uncertainty, being these tools mainly understood as representation techniques. In particular, a key paper published by this research team allows measurements of the quality of each classification system, taking into account particular families of operational and consistent aggregation rules, being therefore the basis for subsequent learning and optimization procedures. This approach is specially significative when classes have no clear borders and large transition zones appear, since in this context a pure statistical analysis may be inappropriate. Hence, particular emphasis is devoted to develop algorithm representation techniques with non probabilistic uncertainty. The project pursues the design of classification aid models by putting these pillars together, to be checked in several scientific fields where we have already some experience, in collaboration with other research groups (stars or cells classification, land cover use, systems reliability, preference representation, etc.) Keywords: Decision making, preference representation, knowledge representation, aggregation information, classification, fuzzy sets, optimization. 1 Objectives Being this project a project on basic research, it must be made clear that the first objective we pursue is the development of models and tools potentially useful for some specific problems, not the practical resolution of these problems. Nevertheless, the policy of this research team has been always to strength scientific links with partners in direct contact to those problems. Without them we can not produce useful results. We think this procedure is in the best ∗ Email: [email protected] TIN2006-06190 scientific tradition and indeed they provide us the inspiration framework for most theoretical objectives. Whenever we get so close to a real implementation, a contract is signed in advance in order to clarify scientific achievements from their industrial implications. In this sense, this team has always stressed the operationality of each approach, avoiding the development of tools that can not be taken by our partners, because its computational or conceptual requirements. There were five main theoretical objectives being declared in the application of this still ongoing project: 1. The bottom aggregative subproject has deserved a special attention, being a main component of the project. In particular, we have stressed the recursive approach for aggregation operations as a constructive approach that contains a relevant proportion of aggregation rules that can be found in practice. Although we have shown also some limits, perhaps the most relevant consequence of our study is the paper that appeared in Fuzzy Sets and Systems [18] pointing out that structure should be made always explicit in any context (objects, criteria, classes, alternatives, etc.) The general model proposed in this paper will become one of the key foundations for next next project we are actually applying to. As a first consequence, this paper offers an interesting explanation of the great dispute that has been created around Atanassov’s ”Intuitionistic” fuzzy sets: it is the absence of such a structure the missing argument that makes a difference between two models with different intuitive support. It is a extremely original ongoing research. In parallel, several studies have been developed on interval fuzzy sets, in collaboration to H. Bustince’s research group at the Public University of Navarra [33, 35]. In addition, we have obtained a functional characterization of migrativity [34] in collaboration to R. Mesiar from Slovakia. 2. The consistency issue has also devoted an attention that has been always present in past projects. In particular, we have developed several algorithms to approximate inconsistent preferences to the closet consistent preference, according to several transitive-based consistencies [7]. Related to consistency we have also presented original approaches to Arrow’s paradox in group decision making [58] together with some positional paper pointing out the role of fuzziness in decision making and Science [19, 60]. 3. In order to deal with the computational problems related to dimensional representation, we have developed an alternative representation approach [51]. Although this approach has been shown useful to estimate criteria weights, we are still working on the uniqueness issue (i.e., which one is the good representation among the family of possible representations. It is again an extremely original research that has lead in the past to the first algorithm to evaluate dimension within the crisp context (published in Journal of Algorithms). 4. Great results have been obtained within the segmentation and coloration subproject, developing and applying our algorithms to remotely sensed images, with the collaboration of G. Biging at the University of California, Berkeley (USA). Improved algorithms have been applied to real images [47, 49, 50]. Classical crisp models have been translated to the fuzzy context, allowing a fuzzy clustering that is conceptually simpler than the equivalent crisp clustering, and more informative due to the structure of regions being created. It is again quite original and it is increasingly cited by other researchers. TIN2006-06190 5. First steps towards a fuzzy verification process have been developed [56, 57], an issue that we think deserve more effort since quite a number of practical situations do not allow an appropriate statistical analysis to check results (quite often the consistency of the supporting argument or algorithm is the only support for a decision). There is still a lot of work ahead, but we are missing a more sophisticated partner to fix the mathematical foundation for a general model, and we are actually trying to introduce some new elements [26, 27]. From a practical point of view, consequences of theoretical results in the subsequent modeling have been tested in different practical frameworks, together with a number of decision making fields that allow a more complete view of the general project that guides this particular three-years research. Additional and relevant results have been obtained in related fields, that not being included in the list of main objectives, will perform the next three-years research (there is for example an underlying absolutely needed research related to graphs and networks as key structures to be taken into account in the next future). The long-term objective of the research group, perhaps never formally stated in a three-years project, is to create a interdisciplinary group with theoretical, technological and human capacity to address every stage of a decision making process, from experimentation, data analysis and representation tools, decision analysis (amalgamating and decomposition), choice and final verification of the process itself and its results. At this point, important results relative to decision making modeling have been obtained in scheduling and social networks. These collaborations have been developed with the Department of Natural Resources at UC Berkeley, the US technological company Smiths Aerospace (Grand Rapids, Michigan), the Department of Astronomy at Complutense University of Madrid, some Non-Governmental Organizations (like Red Cross and Médicos sin Fronteras) and some national energy and transport companies, among others, taking advantage of the interdisciplinary composition of our research group and in some particular cases bringing some complementary economic (and human) support from other institutions. 2 Status of the project Below we include a quite complete list of articles produced during the first two years of the project. It is important to realize that the project has almost 1/3 of its time ahead, so we expect to complete results during 2009 (we plan to ask on time for an extension of the project till December 31 because of the initial delay in the real access to funding. Nevertheless, we think results already obtained are extremely good not only because of the number and quality of publications produced, but because of the maturity reached by the research group, which has extended contacts with other research groups in Madrid, Spain and the whole word. The research group has been able to get involved into this project to new young and senior researchers (some of them barely needed in order to cover the whole decision making process), and has attained major impact in the scientific community. The organization of the 8th international FLINS conference (200 participants, see http://www.mat.ucm.es/congresos/flins2008) including the active participation of leading researchers in the field like L.A. Zadeh, P. Bonissone, W. Pedrycz, J. Kacprzyk, E. Trillas and F. Herrera, among others, and the organization of the 1st FuzzyMAD meeting for the whole fuzzy community in Madrid (40 attendants), had helped the group to get ready to more important scientific objectives. TIN2006-06190 In the present research team we are 12 researchers: V. Cutello, L. Garmendia, D. Gómez, E. Kerre, V. López, J. Montero (I.P.), S. Muñoz, T. Ortuño, J.T. Rodrı́guez (Ph.D. student), B. Vitoriano, J. Yáñez plus E. Roano, recently incorporated. It is indeed relevant the number of collaborations (in terms of joint published papers) with other research groups that the new team (that will hopefully include profs. T. Calvo, L. de Ledesma and A. Pradera plus 2 Ph.D. students) will present as a guarantee for the next three-years project application within the national research framework: • At Complutense University, the research groups of A.I. Gómez de Castro (Dept. of Astronomy), M. Santos (Faculty of Informatics) and J. Tejada (Statistics and Operational Research). • In Spain, the groups of H. Bustince (Public University of Navarra) and L. Escudero (Rey Juan Carlos University) among the rest, but also the groups of E. Carreño (National Geographical Institute), E. Castiñeira and S. Cubillo (Technical University of Madrid), F. Herrera (Granada University), J.L. Garcı́a Lapresta (Valladolid University), L. Martı́nez (University of Jaén), G. Mayor (University of the Balearic Islands), P. Sobrevilla and E. Montseny (Technical University of Catalunya) and E. Trillas (European Centre for Soft Computing, Mieres). • And around the world, A. Amo (GE Aviation Systems, Grand Rapids, Michigan, USA), G. Beliakov (Australia), G. Biging (University of California at Berkeley, USA), K. Cios (moving from the University of Ohio, Toledo, USA), V. Cutello (University of Catania, Italy), B. De Baets (University of Gent, Belgium), J. Fodor (Hungary), E.E. Kerre (University of Gent, Belgium), J. Lu (Australia), A.D. Pearman (University of Leeds, UK) and R.R. Yager (University of New York, USA) A weakness of the present team is the low number of Ph.D. students, but the fact is that during the last years quite a number of students asked us to join our research group, but finally we had to redirect them to join other research teams with Ph.D. grants. Getting Ph.D. grants associated to the new research project we are actually applying to is a major priority. References [1] A. Alonso, L.F. Escudero and M.T. Ortuño : On a stochastic sequencing and scheduling problem. COMPUTERS AND OPERATIONS RESEARCH 34:2604-2624 (2007) [2] A. Alonso, L.F. Escudero and M.T. Ortuño : On Modelling Planning under Uncertainty in manufacturing. STATISTICS AND OPERATIONS RESEARCH TRANSACTIONS 31:109-150 (2007) [3] A. Amo, L. Garmendia, D. Gómez and J. Montero : A spatial classification model for multicriteria analysis. IEEE Symposium on Computational Intelligence in Mulcticriteria Decision Making (IEEE Press, Piscataway); pp. 348-353, ISBN: 1-4222-0702-8 (2007) [4] H. Bustince, E. Barrenechea, M. Pagola, R. Orduña and J. Montero : Special construction of Atanassov’s intuitionistic fuzzy S-implications. Proceedings IWIFSGN 2007 TIN2006-06190 [5] H. Bustince, V. Mohedano, J. Montero and E. Barrenechea : Semiautodualiy in a restricted family of Klir-Folger’s aggregation operators. FUZZY SETS AND SYSTEMS 158:13601377 (2007) [6] J. Castro, D. Gómez and J. Tejada : A project game for PERT networks. OPERATIONS RESEARCH LETTERS 35:791-798 (2007) [7] L. Garmendia and J. Recasens: Approximation of Proximities by Aggregating Tindistinguishability Operators. MATHWARE AND SOFT COMPUTING 3:171-181 (2007) [8] D. Gómez, J. Montero and G, Biging : Accuracy measures for fuzzy classification. EUROFUSE’07 (A Demanda, Jaén); pp. 55-60, ISBN: 978-84-690-4561-9 (2007) [9] D. Gómez, J. Montero and J. Yáñez : Decomposing preference relations. FUZZ-IEEE’07 (IEEE Press., 2007), pp. 1251-1255, ISBN: 1-4244-1210-2 [10] D. Gómez, J. Montero, J. Yánez and C. Poidomani : A graph coloring approach for image segmentation. OMEGA-Int.J.Manag.Sci. 35, 173-183 (2007) [11] L.M. Laita, E. Roanes Lozano and L. de Ledesma: What Machines Can and Cannot Do. Revista de la Real Academia de Ciencias Exactas, Fı́sicas y Naturales, Serie A, Matemáticas 101:133-157 (2007) [12] V. López and J. Montero : Fuzzy specification of software requirements. JCIS’07 (Ass. Intelligent Machinery, Salt Lake City, 2007) [13] V. López and J. Montero : Fuzzy specification of algorithms. EUROFUSE’07 (A Demanda, Jaén); pp. 151-156, ISBN: 978-84-690-4561-9 (2007) [14] V. López and J. Montero : Análisis de requisitos difusos em valoración de inmuebles. CEDI-LFSC’07 (Thomson-Paraninfo, Zaragoza); pp. 181-187. ISBN: 978-84-9732-609-4 (2007) [15] L. Martı́nez and J. Montero : Challenges for improving consensus reaching process in collective decisions. NEW MATHS AND NATURAL COMPUTATION 3:203-217 (2007) [16] I. Martı́nez, B. Vitoriano, A. Fernández and P. Cucala : Statistical dwell time model for metro lines. Urban Transport XIII: Urban Transport and the Environment in the 21st Century. WIT Press, Reino Unido, ISBN: 978-184564-087-3 (2007) [17] J. Montero, D. Gómez and H. Bustince : Atanassov’s intuitionistic fuzzy sets as a classification model. LECTURE NOTES IN ARTIFICIAL INTELLIGENCE 4529:69-75 (2007) [18] J. Montero, D. Gómez and H. Bustince : On the relevance of some families of fuzzy sets. FUZZY SETS AND SYSTEMS 158:2429-2442 (2007) [19] J. Montero, V. López and D. Gómez : The role of fuzziness in decision making. STUDIES IN FUZZINESS AND SOFT COMP.215:337-349(2007) [20] S. Muñoz : Identifying violated maximal cover inequalities in 0-1 problems. Actas del XXX Congreso Nacional de Estadı́stica e Investigación Operativa (2007) TIN2006-06190 [21] E. Roanes Macı́as and E. Roanes Lozano: 3D-extension of Steiner chains problem. MATHEMATICAL AND COMPUTER MODELLING 45:137-148 (2007) [22] E. Roanes Lozano: Sobre la colaboración de sistemas de geometrı́a dinámica y de álgebra computacional y el nuevo sistema Geometry Expressions. Boletı́n de la Sociedad ”Puig Adam” de Profesores de Matemáticas 75:72-90 (2007) [23] E. Roanes Macı́as, E. Roanes Lozano and J.F. Biarge: Extensión a 3D del teorema de Desargues, sustituyendo triángulos por tetraedros. Boletı́n de la Sociedad ”Puig Adam” de Profesores de Matemáticas 75:13-28 (2007) [24] E. Roanes Macı́as and E. Roanes Lozano: Determinación de lugares geométricos, vı́a sintética y computacional, aplicada a lugares de tipo cisoide. Boletı́n de la Sociedad ”Puig Adam” de Profesores de Matemáticas 76:32-52 (2007) [25] E. Roanes Lozano, J. Cabezas, P. Ortega, E. Roanes Macı́as, C. Romo and M. de la V. Vara: Un proyecto para el uso del sistema de cómputo algebraico Máxima en Educación Secundaria. Boletı́n de la Sociedad ”Puig Adam” de Profesores de Matemáticas 76:68-77 (2007) [26] E. Roanes Macı́as and E. Roanes Lozano: A Maple Package for Automatic Theorem Proving and Discovery in 3D-Geometry. LECTURE NOTES IN ARTIFICIAL INTELLIGENCE 4689:171-188 (2007) [27] A. Sols, J.E. Ramı́rez-Márquez, D. Verma and B. Vitoriano : Evaluation of Full and Degraded Mission Reliability and Mission Dependability for Intermittently Operated MultiFunctional Systems. RELIABILITY ENGINEERING AND SYSTEM SAFETY 92:12741280 (2007) [28] J. Yáñez, J. Montero and D. Gómez : Astronomical images: a segmentation algorithm. The World Space Observatory Ultraviolet (WSO/UV) Project, A.I. Gómez de Castro and E. Verdugo, eds. (Ed. Complutense, Madrid); pp. 297-308, ISBN: 978-84-7491 (2007) [29] A. Amo, D. Gómez, J. Montero and G. Biging : Improving fuzzy classification by means of a segmentation algorithm. STUDIES IN FUZZINESS AND SOFT COMP.220:454473(2008) [30] H.Bustince,E.Barrenechea,M.Pagola,R.Orduña and J.Montero : Special construction of Atanassov’s intuitionistic fuzzy S-implications. Proceedings IWIFSGN’07 (Academic Pub. House EXIT,Warsaw); pp. 23-32. ISBN: 978-83-60434-52-9 (2008) [31] H. Bustince, J. Fernández and J. Montero : Grados de solapamiento entre conjuntos difusos. ESTYLF’08, pp. 79-84. ISBN: 978-84-691-5807-4 (2008) [32] H. Bustince, F. Herrera and J. Montero (editores) : Fuzzy Sets and their Extensions (Springer, 2008) [33] H. Bustince, J. Montero, E. Barrenechea and M. Pagola : Laws for conjunctions and disjunctions in interval type 2 fuzzy sets. Proceedings WCCI’08; pp. 1613-1618 (IEEE Press, Piscataway). ISBN:978-1-4244-1819; ISSN: 1098-7684 TIN2006-06190 [34] H. Bustince, J. Montero and R. Mesiar : Migrativity of aggregation operators. FUZZY SETS AND SYSTEMS (in press) [35] H. Bustince, J. Montero, M. Pagola, E. Barrenechea and D. Gómez : A survey on intervalvalued fuzzy sets. STUDIES IN FUZZINESS AND SOFT COMP. (2008) [36] H. Bustince, J. Montero, R. Orduna, M. Pagola and E. Barrenechea : A survey of Atanassov’s Intuitionistic Fuzzy Relations. HANDBOOK OF GRANULAR COMPUTING (Wiley, New York, 2008). ISBN: 978-0470-03554-2 [37] J. Castro, D. Gómez and J. Tejada : A project game for PERT networks. OPERATIONS RESEARCH LETTERS (in press) [38] J. Castro, D. Gómez and J. Tejada : The use of proportional rule applied to durations for slack distribution in a PERT network. EUROPEAN JOURNAL OF OPERATIONAL RESEARCH 187:556-570 (2008) [39] J. Castro, D. Gómez and J. Tejada : A polynomial rule for the problem of sharing delay costs in PERT networks. COMPUTERS AND OPERATIONS RESEARCH 35:2376-2387 (2008) [40] D. Dı́az, A. Garmendia, L. Garmendia and A. Salvador : Diseño mediante lógica fuzzy de un sistema de determinación de especies de plantas de la familia Primula. JOURNAL OF MATHEMATICS AND DESIGN 9:7-22 (2008) [41] L.F. Escudero and S. Muñoz : Improvements on the extended rapid transit network design problem modelling. Technical Reports on Statistics and Decision Sciences, TR08/01, Universidad Rey Juan Carlos, Spain [42] L.F. Escudero and S. Muñoz : An approach for solving a modification of the extended rapid transit network design problem. TOP (in press) [43] A. Felipe, M.T. Ortuño and G. Tirado : Neighborhood structures to solve the double traveling salesman problem (TSP) with multiple stacks using local search. COMPUTATIONAL INTELLIGENCE IN DECISION AND CONTROL 1:701-706 (2008) [44] M.A. Fernández de Sevilla, L.M. Laita, E. Roanes Lozano and L.A. Gonzalez Sotos: An Expert System Devoted to Automated Music Identification and Recognition. In: J. Shen, J. Shepherd, B. Cui, L. Liu, editors: Intelligent Music Information Systems 80-101 (2008) [45] A. Garmendia, A. Salvador and L. Garmendia : The importance of the intensity and frequency of perturbations on the germination delay. MATHEMATICAL BIOSCIENCES 211:153-165 (2008) [46] L. Garmendia, A. Salvador and J. Montero : Computing a T-transitive opening of a proximity. COMPUTATIONAL INTELLIGENCE IN DECISION AND CONTROL 1:157-162 (2008) [47] D. Gómez, G. Biging and J. Montero : Accuracy statistics for judging soft classification. INTERNATIONAL JOURNAL OF REMOTE SENSING 29:693-709 (2008) TIN2006-06190 [48] D. Gómez and J. Montero : Fuzzy sets in remote sensing classification. SOFT COMPUTING 12:243-249 (2008) [49] D. Gómez and J. Montero : Determining the accuracy in supervised fuzzy classification problems. COMPUTATIONAL INTELLIGENCE IN DECISION AND CONTROL 1:411416 (2008) [50] D. Gómez, J. Montero and G. Biging : Improvements to remote sensing using fuzzy classification, graphs and accuracy statistics. PURE AND APPLIED GEOPHYSICS 165:1555-1575 (2008) [51] D. Gómez, J. Montero and J. Yánez : An algorithmic approach to preference representation. UNCERT.,FUZZ.AND KNOW.-BASED SYST. 16-1-18 (2008) [52] D. Gómez, J. Montero and S. Muñoz : Fuzzy information representation for decision aiding. Proceedings IPMU’08 (Málaga,Spain); pp. 1425-1430. ISBN: 978-84-612-3061-7 (2008) [53] V. López, A. Del Monte and J. Montero : Fuzzy logic in real estate valuation. COMPUTATIONAL INTELLIGENCE IN DECISION AND CONTROL 1:1021-1026 (2008) [54] V. López and J. Montero : Fuzzy logic for formal specification of systems. Proceedings ISA’08, pp. 234-237. ISBN: 978-972-8924-67-6 (2008) [55] V. López and J. Montero : REV, valuation and price adjustment in a fuzzy logic framework. Proceedings ISKE’08, pp. 640-645, vol. 1 (IEEE Press, Beijing, 2008). ISBN: 9781-4244-2196-1 (2008) [56] V. López and J. Montero: Software engineering specification under fuzziness. MULTIPLEVALUED LOGIC AND SOFT COMPUTING (in press) [57] V. Lopez, J. Montero, L. Garmendia and G. Resconi : Specification and computing states in fuzzy algorithms. INT. J. UNCERTAINTY, FUZZINESS AND KNOWLEDGE-BASED SYSTEMS 16:301-336 (2008) [58] J. Montero : The impact of fuzziness in social choice paradoxes. SOFT COMPUTING 12:177-182 (2008) [59] J. Montero : Soft Sciences versus Crisp Sciences, a look into the future of Science. Proceedings ISKE’08, pp. 1328-1387, vol. 2 (IEEE Press, Beijing, 2008). ISBN: 978-1-42442196-1 (2008) [60] J. Montero : Fuzzy logic and science. STUDIES IN FUZZINESS AND SOFT COMPUTING (in press) [61] J. Montero, D. Gómez, H. Bustince and E. Barrenechea : The underlying structure in Atanassov’s IFS. Developments in FS, IFS, GN and Related Topics, vol. 1 (Academic Publishing House EXIT, Warsaw); pp. 243-252. ISBN: 978-83-60434-52-9 (2008) TIN2006-06190 [62] E. Roanes Lozano, A. Martı́nez Zarzuelo, A. Garcı́a Alvarez and E. Roanes Macı́as: Unas reflexiones sobre el reconocimiento de rutas en mapas ferroviarios y teorı́a de grafos. Boletı́n de la Sociedad ”Puig Adam” de Profesores de Matemáticas 78:79-90 (2008) [63] E. Roanes Lozano, L.M. Laita and E. Roanes Macı́as: Un sistema predictivo para la toma de decisiones inspirado por el modelo gravitacional. Boletı́n de la Sociedad ”Puig Adam” de Profesores de Matemáticas 79:43-55 (2008) [64] E. Roanes Lozano, L.M. Laita and E. Roanes Macı́as: A Symbolic-Numeric Approach to MPL Continous Logic and to Rule Based Expert Systems whose Underlying Logic is MPL. The Open Applied Mathematics Journal 11:126-133 (2008) [65] E. Roanes Macı́as, E. Roanes Lozano and J. Fernández Biarge: Extensión natural a 3D del teorema de Pappus y su configuración completa. Boletı́n de la Sociedad ”Puig Adam” de Profesores de Matemáticas 80:38-56 (2008) [66] E. Roanes Lozano and E. Roanes Macı́as: A Simple Geometric Theorem with a Constructive Configuration Whose Truthfulness Depends on the Base Field Considered. ADVANCES IN COMPUTATIONAL SCIENCES AND TECHNOLOGY (in press) [67] E. Roanes Lozano, L.M. Laita, E. Roanes Macı́as, M.J. Wester, J.L. Ruiz and C. Roncero: Evolution of Railway Network Flexibility: the Spanish Broad Gauge Case. MATHEMATICS AND COMPUTERS IN SIMULATION (in press) [68] E. Roanes Lozano, L.M. Laita and E. Roanes Macı́as: A Groebner Bases Based Manyvalued Modal Logic Implementation in Maple. LECTURE NOTES IN ARTIFICIAL INTELLIGENCE 5144:170-183 (2008) [69] E. Roanes-Lozano, A. Hernando, L.M. Laita and E. Roanes Macı́as: A Shell for RuleBased Expert Systems Development Using Groebner Bases-Based Inference Engines COMPUTATIONAL INTELLIGENCE IN DECISION AND CONTROL 1:769-774 (2008) [70] J.T. Rodrı́guez, B. Vitoriano, J. Montero and A. Omaña : A decision support tool for internacional relief operations. COMPUTATIONAL INTELLIGENCE IN DECISION AND CONTROL 1:805-810 (2008) [71] J.T. Rodrı́guez, B. Vitoriano, J. Montero and D. Gómez : Modelling Bipolar Multicriteria Decision Making. Proceedings IEEE MCDM’09 (IEEE Press, in press). [72] D. Ruan, J. Montero, J. Lu, L. Martı́nez, P. D’hondt and E.E. Kerre (editores) : Computational Intelligence in decision and control vol. 1 (2009) [73] B. Vitoriano, M.T. Ortuño and A.F. Ruiz-Rivas : A goal programming model for humanitarian aid distribution. COMPUTATIONAL INTELLIGENCE IN DECISION AND CONTROL 1:811-816 (2008) [74] J. Yáñez, S. Muñoz and J. Montero : Graph coloring inconsistencies in image segmentation. COMPUTATIONAL INTELLIGENCE IN DECISION AND CONTROL 1:435-440 (2008)