The Ordered Weighted Averaging Operators is the first book in the literature on the increasingly popular Ordered Weighted Averaging (OWA) operators. These OWA operators make it possible to change the form of aggregation from the "pessimistic" minimum-type aggregation through all intermediate types including the conventional arithmetic mean and nonconventional aggregations, to the "optimistic" maximum-type aggregations. Included in this edited book are contributions from a number of fields where these operators have been applied. These fields are decision analysis under uncertainty, learning and classification, multi-person decision making and consensus formation, and flexible database querying and information retrieval.