Case Study Comparison of Weighting-Rating-Calculating, Best Value, and Choosing by Advantages for Bidder Selection Annett Schöttle 1 and Paz Arroyo, Ph.D. 2 Abstract: Selecting the best bidder during a tendering procedure is key to project success. However, the methods used for decision making and their implications are not well understood. This study presents a theoretical and case-based comparison of three multicriteria decision- making (MCDM) methods—weighting-rating-calculating (WRC), best value selection (BVS), and choosing by advantages (CBA)—to illustrate the impact of these methods on the tendering procedure. The authors explain the benefits of using CBA and why it is superior to WRC and BVS for avoiding the speculative behavior of bidders. The results of the applied sensitivity analysis provide evidence that superior methods, such as CBA, do not mix cost and value, because generally the price significantly impacts the decision disregarding technical performance. Therefore assigning a weighted score to the submitted price (WRC) and dividing price by score (BVS) are risky because bidders may try to compensate for a poorly made technical proposal by proposing a low bid price. In comparison, CBA does not mix cost and value, provides a transparent and reproducible framework to support the tendering procedure, and overcomes speculative bidder behavior. Therefore the authors recommend that public owners study and apply CBA. DOI: 10.1061/(ASCE)CO.1943-7862.0001342. © 2017 American Society of Civil Engineers. Author keywords: Tendering procedure; Multicriteria decision-making; Weighting-rating-calculating; Best value selection; Choosing by advantages; Contracting. Introduction Public tendering procedures require fair and objective competi- tion in the process used to select the contractor and therefore must select the project team based on a regulated system. Therefore the evaluation of submitted proposals must be transparent and compre- hensible. Flyvbjerg et al. (2003) studied transport infrastructure megaprojects and determined that the difference between actual and estimated investment cost often included a 50–100% overrun. This overrun may have been caused by an underestimated proposal that contained speculation and resulted in conflicts later in the pro- cess (Bruzelius et al. 2002; Schöttle and Gehbauer 2013). To avoid claims and speculation against the public tendering procedure, the methods used to assess the process and factors used to evaluate the proposals should be clearly defined prior to the request for the proposal. Numerous authors have suggested a multicriteria ap- proach to select the project team when the tendering procedure oc- curs in the public sector (Abdelrahman et al. 2008; Asmar et al. 2009; Ballesteros-Pérez et al. 2015, 2016; Kumaraswamy 1996; Migliaccio et al. 2009; Waara and Bröchner 2006). Weighting- rating-calculating (WRC) is a common method used to evaluate proposals (Asmar et al. 2009; Ballesteros-Pérez et al. 2015). Al-Reshaid and Kartam (2005) presented a case study that used WRC for the prequalification. Asmar et al. (2009) simulated WRC-evaluated proposals with Monte Carlo methods to select an alliance team, and Birrell (1988) used WRC for evaluating a bidder based on past performance. Furthermore, applications of WRC also exist for the procurement method (Love et al. 2012). Although Suhr (1999) introduced choosing by advantages (CBA) almost 30 years ago, the method is not well discussed in construction research and practice. Bakht and El-Diraby (2015) re- viewed the articles published in the last 50 years of the Journal of Construction Engineering and Management to illustrate the evolu- tion of the decision models and tools that have been used in the construction industry. They identified the following trends that could alter the decision-making process: (1) network of decision makers; (2) positivism and phenomenology; (3) probabilistic mod- els instead of purely deterministic models; (4) rational and axio- matic techniques instead of judgement; and (5) integrated project delivery system. This literature review did not include the CBA method; therefore, CBA is not well known although it is a useful method to the identified trends. Several publications have addressed the application of CBA dur- ing the design process (Grant 2007; Parrish and Tommelein 2009; Arroyo et al. 2014b, 2016b; Kpamma et al. 2015; Kpamma et al. 2016). Using multiple baseline testing, Arroyo et al. (2016a) con- ducted the first experimental study to compare the practical use of WRC and CBA in the design process in terms of time to achieve consensus, method satisfaction, personal frustration, and perceived frustration from others. Five groups of three persons each decided among four alternatives. Each group made the same 12 decisions. Cost was not a component of any of the decisions. The first deci- sions were made using WRC, and then the CBA method was in- troduced and decisions were made using CBA. Each group began using CBA with an interval of one question. A majority (86%) of the participants preferred the use of CBA because it was less sub- jective and more transparent, and less conflict occurred among the decision makers. Overall, the decision makers needed less time to reach consensus and felt less frustrated. Haapasalo et al. (2015) used CBA to compare procurement models to select the optimal contract type for road maintenance, 1 Ph.D. Candidate, Institute of Technology and Management in Construction, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany (corresponding author). E-mail: annett.schoettle@protonmail.com 2 Assistant Professor, Dept. of Construction Engineering and Manage- ment, Pontificia Universidad Cat´ olica de Chile, 7820436 Santiago, Chile. E-mail: parroyo@ing.puc.cl Note. This manuscript was submitted on October 17, 2016; approved on February 13, 2017; published online on May 15, 2017. Discussion period open until October 15, 2017; separate discussions must be submitted for individual papers. This paper is part of the Journal of Construction En- gineering and Management, © ASCE, ISSN 0733-9364. © ASCE 05017015-1 J. Constr. Eng. Manage. J. Constr. Eng. Manage., 2017, 143(8): -1--1 Downloaded from ascelibrary.org by Pontificia Universidad Catolica de Chile (UC) on 05/16/17. Copyright ASCE. For personal use only; all rights reserved.