Decision making under uncertainty in construction projects using social judgment theory

Analyzing and modeling uncertainty have become a major focus of interest in construction engineering and management. The various approaches considered in the past have included probabilistic methods and fuzzy set theory. Howe ver, none of these methods incorporate human judgment in making decisions u nder uncertainty. This paper presents an approach to analyzing and modeling uncertainty based on a theory of human judgment, termed Social Judgment Th eory (SJT). SJT involves the development of a mathematical model of the jud gment process of individuals. SJT is readily understood and accepted by hum an judgment theorists and has been applied in a variety of disciplines that involve decision making. The paper describes the basics of SJT and further utilizes it to model the decision making process of human project experts under uncertain situations. Techniques used to improve human judgment throu gh the use of cognitive feedback until an optimal model is developed are de scribed. The paper then demonstrates how SJT is applied to predict the expe cted quantity variance of construction projects under uncertainty based on the judgment of construction experts.