An interval type-2 fuzzy MCDM model for work package subcontractor prequalification

The inherent role of the Main Contractors (MCs) and their responsibility to employers force them to consider an appropriate mechanism for evaluating the subcontractors (SCs). The past few decades witnessed the gradual prevalence of fuzzy set theory in different industries. The construction industry was not an exception either. It is in use now for SCs prequalification thanks to its competence in covering the flaws underlying the SC selection methods. Most previous researches employed Type-1 Fuzzy Sets (T1FSs) in SCs prequalification models. But, the result of the applying TIFSs to solve a SC prequalification could be simply misleading because it is principally a group (Multi-Criteria Decision Making) MCDM problem. An important limitation of T1FS assures the fact that it can handle the decision-making problem of only one person because its membership function is crisp, relying on his subjective viewpoint, and deterring it from revealing differing views among the experts. We aim to introduce a novel SCs prequalification method using Interval Type-2 Fuzzy Sets (IT2FSs) in a bid to rectify the linguistic flaws as well as differences of the experts' views. Therefore, an integration of two methods, namely "Shannon Entropy Weight" and "Technique for Order Performance by Similarity to Ideal Solutions," is used under IT2FS for solving the SC prequalification problem. In addition, a real case is considered to demonstrate the effectiveness of the proposed method.