Application of GIS-Based OWA Method to Suitability Evaluation ofConstruction Land in Tangshan City

Ordered weighted averaging (OWA) is a relatively new Multi-Criteria Evaluation (MCE) method. Ordinary, Boolean overlay represents the extreme cases with no tradeoff, Boolean AND operator represents the MIN decision making risk, and Boolean OR operator represents the MAX decision-making risk; WLC method is an averaging risk decision-making with full tradeoff among criteria; OWA method can obtain any results from the MIN risk to MAX risk with appropriate tradeoff. In GIS-based OWA method, both criteria weights and order weights are considered, which makes the calculation and decision strategy more complicated. Calculation method of order weights based on Orness, and construction method of comparison matrix for criteria weights based on analytical hierarchy program (AHP), are introduced; decision-making strategy of GIS-based OWA method is discussed through analyzing OWA evaluation procedure, the relationship between decision-making risk and tradeoff is investigated. As an example, GIS-based OWA method is applied to Tangshan City.