“…Such imprecisely defined sets of objects are called fuzzy sets . For example, there have been a number of applications aiming at implementing fuzzy forms of the WLC model (e.g., Paez et al 2006;Vadrevu et al 2010), AHP (e.g., Anagnostopoulos and Vavatsikos 2012;Kordi and Brandt 2012), compromise programming (Simonovic and Nirupama 2005), and PROM-ETHEE (e.g., Chou et al 2007). There are two main types of approaches for performing a combination of linguistic information: approximation and symbolic methods (Malczewski 2002).…”