Delphi Technique

What is this technique about

It is one of the most widely used techniques for prospective analysis by using expert assessment since it overcomes the biases and limitations of a single individual and allows to rely on the intersubjective judgment of an experts’ panel. It is a particularly versatile technique, very suitable for technological prediction but also to face situations of uncertainty or when there is a lack of objective information on a subject.

Where does it come from 

The Delphi method was described for the first time in 1962, in the memorandum entitled “An experimental application of the Delphi method to the use of experts”, a simplified version of the study initiated in 1948 by the Rand Corporation, led by Norman Dalkney and Olaf Helmer, as an instrument to make predictions about nuclear catastrophe scenarios for the United States Army.

For which purposes it is used (why in your engineering teaching)

The technique is based on a successive series of consultations with a group of experts on a topic, identifying the key variables that influence its development and the probability with which certain changes can be produced in each one of these variables. It is particularly useful for problem solving and computerized problem solving.

How to use it

Implementation includes between 2 and 5 successive questionnaires to a group of around 25 people (between 15 and 100 individuals, depending on the target group) chosen among experts on the subject under investigation or people directly involved in an issue.

The process begins with the selection of the participants, which is the key element of the project, since they must have sufficient knowledge to be able to make relevant predictions and the necessary involvement to maintain their participation throughout the research process.

From that point, there are two main implementation sequences, depending on the objective and target group involved,

1. 1. Expert panel for technical & technological prediction:
      
      1. Identify the key variables affecting the subject (i.e. the 3 or the 5 most important variables).
      2. Develop a combined list of the variables.
      3. Check the combined list and evaluate the relative importance of each identified variable (rank, rating, etc.).
      4. Obtaining responses from the experts and creation of a ranked list of variables (averages).
      5. Show the results of the consultation of step D and discuss agreement-disagreement with results and other relevant measures (i.e. relevance, validity, etc.).
   2. Use for problem identification and problem solving.
      
      1. Divide the participants in small collaborative groups.
      2. Ask each individual to list the most relevant aspects (problems, uncertainties, etc.) affecting the subject or topic.
      3. Then ask each small group to analyse the individual responses, creating categories and subcategories. Reach group consensus about the relative importance (and/or priority, relevance, etc.) of each identified category (rank, punctuation, etc.).
      4. All small groups share their work with the large group. Each small group discuss the global results, developing possible scenarios/ alternatives.
      5. Final round in which small groups evaluate the scenarios or alternatives developed by all groups, discussing their agreement-disagreement with them (i.e. probability, desirability, etc.) until reaching consensus.