ABSTRACT
Historically, decision-makers have used expert opinion to supplement insufficient data. Relatively cheap and virtually inexhaustible (Cook, 1991), experts greatly influence decisions in key subject matters such as political, financial, legal, and social issues. Additionally, a major source of information in estimating the parameters of risk and reliability models is expert judgment. Cases involving new process or product design, very rare events, and proceedings that are beyond our direct experience, call for the use of expert opinion as a surrogate information source. The evaluation of expert judgment quality starts with a clear definition of ‘expert(s)’. For the purpose of this paper, an ‘expert’ is broadly defined as a field professional that will assist the analysts or decision makers to determine the unknown quantity of interest. Besides expressing their subjective judgments directly, experts can use prototypes, models, simulations, destructive and nondestructive tests (among other tools) to gather information, acquire data, gain pertinent practical knowledge, and to carry out a specified set of tasks proficiently. The association of expert’s attributes to the quality of expert judgments is acknowledged in most of the studies. Attributes are the characteristics and qualities relating to an individual. Specific attributes are used to differentiate between experts and novices. However, the identification and selection of experts is subjective; a unique perception of the qualifications is reported in different studies to name an individual the ‘expert’. According to Booker and Meyer (1996), expert opinion is used in two ways:
[1] Structuring of technical problems including the determination of relevant information for analyses such as key input and output variables
as well as proper assumptions and evaluation techniques.
