Final answer:
The method described in the question is called the Delphi method. It is a group decision-making and forecasting technique that involves experts.
Step-by-step explanation:
The method described in the question is called the Delphi method. It is a group decision-making and forecasting technique that involves experts. In this method, a large number of experts provide their forecasts and assumptions.
An intermediary passes these forecasts and assumptions to the other experts, who then revise their own forecasts. This iterative process continues until a composite forecast that is acceptable to the group is reached.