This book constitutes the proceedings of the 6th International Conference on Modeling Decisions for Artificial Intelligence, MDAI 2009, held on Awaji Island, Japan, in November/December 2009. The 28 papers presented in this book together with 5 invited talks were carefully reviewed and selected from 61 submissions.

Invited Papers.- Interactive Robust Multiobjective Optimization Driven by Decision Rule Preference Model.- g-BDI: A Graded Intensional Agent Model for Practical Reasoning.- Modeling Ambiguity Averse Behavior of Individual Decision Making: Prospect Theory under Uncertainty.- Generalized Bags, Bag Relations, and Applications to Data Analysis and Decision Making.- The Relationship between Interval, Fuzzy and Possibilistic Optimization.- Regular Papers.- Decision Making in Voting Games: An Insight into Theory and Practice.- A Lyapunov-Type Theorem for Nonadditive Vector Measures.- A Formal Theory of Cooperative TU-Games.- The Functionality-Security-Privacy Game.- Toward the Theory of Cooperative Games under Incomplete Information.- Comparison of Data Structures for Computing Formal Concepts.- Using Conditional Random Fields for Decision-Theoretic Planning.- Interactive Decision Making for Hierarchical Multiobjective Linear Programming Problems.- A Perception-Based Portfolio Under Uncertainty: Minimization of Average Rates of Falling.- A Differential Evolution Based Time-Frequency Atom Decomposition for Analyzing Emitter signals.- Combining Various Methods of Automated User Decision and Preferences Modelling.- Target-Oriented Decision Analysis with Different Target Preferences.- A Novel Method for Multibiometric Fusion Based on FAR and FRR.- Performance Evaluation of TEWA Systems for Improved Decision Support.- Discounting and Combination Scheme in Evidence Theory for Dealing with Conflict in Information Fusion.- Evaluation Based on Pessimistic Efficiency in Interval DEA.- Stochastic Facility Construction Problem with Preference of Candidate Sites.- A Consensus Reaching Model for Web 2.0 Communities.- Refinement Properties in Agglomerative Hierarchical Clustering.- Some Pairwise Constrained Semi-Supervised Fuzzy c-Means Clustering Algorithms.- PCA-Guided k-Means with Variable Weighting and Its Application to Document Clustering.- Partial Symbol Ordering Distance.- Situation Recognition and Hypothesis Management Using Petri Nets.- A Hybrid Algorithm Based on Tabu Search and Ant Colony Optimization for k-Minimum Spanning Tree Problems.- Dynamic Neighborhood Selection for Nonlinear Dimensionality Reduction.- A Consistency-Constrained Feature Selection Algorithm with the Steepest Descent Method.- A Heuristic Algorithm for Attribute Reduction Based on Discernibility and Equivalence by Attributes.- Multiobjective Multiclass Soft-Margin Support Vector Machine and Its Solving Technique Based on Benson’s Method.

This book constitutes the proceedings of the 6th International Conference on Modeling Decisions for Artificial Intelligence, MDAI 2009, held on Awaji Island, Japan, in November/December 2009. The 28 papers presented in this book together with 5 invited talks were carefully reviewed and selected from 61 submissions. The topics covered are aggregation operators, fuzzy measures and game theory; decision making; clustering and similarity; computational intelligence and optimization; and machine learning.