An extended minimax disparity to determine the OWA operator weights Gholam R. Amin a, * , Ali Emrouznejad b a Postgraduate Engineering Center, Islamic Azad University of South Tehran Branch, Tehran, Iran b Operations and Information Management Aston Business School, Aston University, Birmingham B4 7ET, UK Received 31 May 2006; accepted 30 June 2006 Available online 8 August 2006 Abstract This paper contributes to extend the minimax disparity to determine the ordered weighted averaging (OWA) model based on linear programming. It introduces the minimax disparity approach between any distinct pairs of the weights and uses the duality of linear programming to prove the feasibility of the extended OWA operator weights model. The paper finishes with an open problem. Ó 2006 Elsevier Ltd. All rights reserved. Keywords: OWA operator weights; Duality of linear programming 1. Introduction The ordered weighted averaging (OWA) operator was introduced by Yager (1988, 1993) provides a unify- ing framework for the traditional decision making approaches. The OWA operator affords a new information aggregation technique and has already aroused considerable research interest (Liu, 2006). For example, in machine scheduling optimization, the OWA operator is particularly useful because the amount of compensa- tion can be adjusted freely (Yager & Filev, 1994). An important issue related to the theory and application of OWA operators is the determination of the weights of the operators (Fuller & Majlender, 2003; O’Hagan, 1988; Wang & Parkan, 2005). Wang and Par- kan (2005) proposed a simple and effective linear programming based approach, called minimax disparity approach, for generating OWA operator weights. This paper improves their proposed LP to obtain as close possible as weights. The paper organized as follows: Section 2 explains Wang and Parkan (2005) minimax model. An improved minimax model is given in Section 3. Section 4 illustrates the model applicability by a numerical example. An open problem and conclusion remarks are given in Sections 5 and 6, respectively. 0360-8352/$ - see front matter Ó 2006 Elsevier Ltd. All rights reserved. doi:10.1016/j.cie.2006.06.006 * Corresponding author. E-mail address: G_Amin@azad.ac.ir (G.R. Amin). Computers & Industrial Engineering 50 (2006) 312–316 www.elsevier.com/locate/dsw