A Framework for Aggregation of Heterogeneous Experts' Opinions in Construction Risk Assessment

• Author / Creator

  Monzer, Natalie

• Construction companies constantly seek to improve risk analysis techniques to determine projects' risk contingency. The construction risk assessment practice relies on heterogeneous experts' opinions in a group decision making (GDM) process to determine the risk probabilities and impacts on a project. In this research, the risk probabilities and impacts are expressed as linguistic terms represented by fuzzy sets, which better represents the uncertainty in experts' risk assessment. However, the current GDM process obtains the experts' collective risk assessment through the consensus reaching process (CRP), which has several limitations, such as being a time consuming procedure. This research improves construction risk assessment GDM by introducing a structured aggregation framework to combine heterogeneous experts' risk assessments. During the aggregation process, the industry common practice in order to represent the heterogeneous experts' different expertise level is to assign experts' importance weights. However, previous literature methods for assigning heterogeneous experts' importance weights are subjective and biased. Therefore, there is a lack of a structured approach for assessing experts' expertise level in construction risk assessment. The aggregation framework illustrated in this thesis presents a systematic and flexible multi-step methodology to assess heterogeneous experts' expertise level and assign experts' importance weights in the construction risk assessment GDM aggregation process. The methods used in the aggregation framework advance the practical application of evaluating heterogeneous experts in construction, while the combination of experts' risk assessments through aggregation advances construction industry GDM practice. A case study with actual project data demonstrates the steps involved in the aggregation framework, and analyzes the most suitable aggregation operator to be implemented in the context by comparing the project risk contingency results to Monte Carlo Simulation (MCS) results. The main contributions of this paper are: introducing a clear and consistent list of criteria, metrics and scales of measure to evaluate experts' risk assessment expertise; developing a method to weight experts' importance in risk assessment according to their expertise level; and improving construction risk assessment GDM by introducing a structured framework for construction risk assessment that combines heterogeneous experts' assessments through aggregation.

• Subjects / Keywords

  • Decision Making
  • Risk Management
  • Fuzzy Sets
  • Construction
  • Heterogeneity

• Graduation date

  Spring 2018

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R38G8FZ61

• License

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