This volume contains the papers selected for presentation at the 1st Conference onModelingDecisionsforArti?cialIntelligence(MDAI2004),heldinBarcelona, Catalonia, August 2 4, 2004. The aim of this conference was to provide a forum for researchers to discuss models for information fusion (aggregation operators) and decision, to examine computational methods and criteria for model selection and determination, and to stimulate their application in new contexts. Fifty-three papers were submitted to the conference, from 19 di?erent co- tries. Each submitted paper was reviewed by at least two experts on the basis of technical soundness, originality, signi?cance and clarity. Based on the review reports, 26 papers were accepted for publication in this volume. Additionally, this volume contains the plenary talks given at the conference. We would like to express our gratitude to the members of the program c- mittee as well as to all reviewers for their work. We thank Alfred Hofmann, from Springer-Verlag,who supported the publication of these proceedings in the LNAI series. The conference was supported by the Catalan Association for Arti?cial Intelligence (ACIA), the European Society for Fuzzy Logic and Technology (EUSFLAT), the Japan Society for Fuzzy Theory and Intelligent Informatics (SOFT), the IEEESpanish Chapter,the Spanish Council for Scienti?c Research (CSIC) and the Generalitat de Catalunya (AGAUR 2002XT 00111).

Inhalt
Invited Talks.- to RoboCup Research in Japan.- Fuzzy Integrals.- Fuzzy Qualitative Models to Evaluate the Quality on the Web.- Multisets and Fuzzy Multisets as a Framework of Information Systems.- Regular Papers.- Stock Price Forecasting: Statistical, Classical and Fuzzy Neural Network Approach.- Wavelet Time Shift Properties Integration with Support Vector Machines.- A Study on Weighting Training Patterns for Fuzzy Rule-Based Classification Systems.- A Machine Learning Approach for Modeling Algorithm Performance Predictors.- A Novel Network Traffic Analysis Method Based on Fuzzy Association Rules.- Quantum Computing Based Machine Learning Method and Its Application in Radar Emitter Signal Recognition.- Modeling the Distributed Control of the Lower Urinary Tract Using a Multiagent System.- Mining Diagnostic Taxonomy Using Interval-Based Similarity from Clinical Databases.- Combining Multiple Classifiers Using Dempster's Rule of Combination for Text Categorization.- An Empirical Analysis of Assessment Errors for Weights and Andness in LSP Criteria.- Reliability of LSP Criteria.- Unsupervised Aggregation by the Choquet Integral Based on Entropy Functionals: Application to the Evaluation of Students.- Preservation of Distinguished Fuzzy Measure Classes by Distortion.- Decision Modelling Using the Choquet Integral.- Measurements of Consensus in Multi-granular Linguistic Group Decision-Making.- On Detecting Interactions in Hayashi's Second Method of Quantification.- A Generalization of Symbolic Data Analysis Allowing the Processing of Fuzzy Granules.- A Learning Procedure to Estimate Missing Values in Fuzzy Preference Relations Based on Additive Consistency.- Decision Making in a Dynamic System Based on Aggregated Fuzzy Preferences.- Object Positioning Based on Partial Preferences.- A Comparative Study of Clustering Methods for Long Time-Series Medical Databases.- Fuzzy Multiset Model and Methods of Nonlinear Document Clustering for Information Retrieval.- A Feature Weighting Approach to Building Classification Models by Interactive Clustering.- A Framework for Representation and Manipulation of Vague Knowledge.- Comparing Transitive Closure with a New T-transitivization Method.- On the Interpretation of Some Fuzzy Integrals.