<P> The Delphi method (/ ˈdɛlfaɪ / DEL - fy) is a structured communication technique or method, originally developed as a systematic, interactive forecasting method which relies on a panel of experts . The experts answer questionnaires in two or more rounds . After each round, a facilitator or change agent provides an anonymised summary of the experts' forecasts from the previous round as well as the reasons they provided for their judgments . Thus, experts are encouraged to revise their earlier answers in light of the replies of other members of their panel . It is believed that during this process the range of the answers will decrease and the group will converge towards the "correct" answer . Finally, the process is stopped after a predefined stop criterion (e.g. number of rounds, achievement of consensus, stability of results) and the mean or median scores of the final rounds determine the results . </P> <P> Delphi is based on the principle that forecasts (or decisions) from a structured group of individuals are more accurate than those from unstructured groups . The technique can also be adapted for use in face - to - face meetings, and is then called mini-Delphi or Estimate - Talk - Estimate (ETE). Delphi has been widely used for business forecasting and has certain advantages over another structured forecasting approach, prediction markets . </P> <P> The name "Delphi" derives from the Oracle of Delphi, although the authors of the method were unhappy with the oracular connotation of the name, "smacking a little of the occult". The Delphi method is based on the assumption that group judgments are more valid than individual judgments . </P>

The delphi method of forecasting is useful​ when