The Delphi Technique An Experimental Evaluation

Much research has been devoted to the Delphi technique. However, very little substantive work has been done on the subject of Delphi accuracy. The purpose of this effort was to test the accuracy of Delphi vs the conference method in making long-range forecasts. College students were used to form Delphi and conference groups that predicted the point spreads of college football games far in advance of play. The results substantiate the claim that Delphi outperforms conference methods on the basis of accuracy for long-range forecasting. For several decades organizations have attempted to amass the talents of groups of individuals in an effort to combine their individual skills and improve decision making. Group decisions are necessary when the scope of a problem is such that no one individual has sufficient expertise and knowledge to effect a solution. However, the traditional process of grouping these “experts” together has caused a number of counterproductive side effects. The Delphi technique was developed at the RAND Corporation in 1950 by Dalkey and his associates to eliminate many of the negative effects related to the use of interacting groups for decision making (especially long-range forecasting) [3]. The purpose of the research reported here was to investigate the forecast accuracy of the Delphi technique vs the conference method under differing levels of group knowledge concerning the forecast objectives. Van de Ven [14] has identified several major factors that inhibit the performance of interacting groups. Previous research substantiates the effects of these factors. Among them is the tendency of low-status members to “go along” with the opinions of high-status members in spite of contrary feelings [ 131. Group pressures for conformity also negatively affect the participants [8]. Interacting groups have a tendency to “fall into a rut” and pursue a single train of thought for long periods [.5]. Also, dominant personalities have a tendency to influence the group [l]. Often, compromise decisions are reached rather than consensus decisions when interacting groups are employed. The Delphi technique was developed to overcome the problems of interacting groups. The participants utilize written responses. Face-to-face contact is not required. Therefore the technique offers significant advantages. Delphi prevents domination by high-status participants or strong personalities. The judgments of individuals hostile to one another WALTER E. RIGGS is Assistant Professor of Management Department, Georgia State University, Atlanta, Georgia.