On the Use of Weighted Linear Combination Method in GIS: Common and Best Practice Approaches

TLDR

The weighted linear combination (WLC) technique is a widely used decision rule for creating composite maps in GIS, yet it is frequently applied without a full understanding of its underlying assumptions, leading to incorrect or dubious results in many case studies. This paper critically reviews current GIS/WLC practices and proposes a best‑practice approach to ensure proper application.

Abstract

The weighted linear combination (WLC) technique is a decision rule for deriving composite maps using GIS. It is one of the most often used decision models in GIS. The method, however, is frequently applied without full understanding of the assumptions underling this approach. In many case studies, the WLC model has been applied incorrectly and with dubious results because analysts (decision makers) have ignored or been unaware of the assumptions. This paper provides a critical overview of the current practice with respect to GIS/WLC and suggests the best practice approach.