Air Vehicle Safety Prevention and Protection System (AVSAPPS)

 Unit 4 Discussion Board

Delphi and Nominal Group Decision-Making Techniques

The Delphi method is a structured, iterative process for converging on a solution or consensus. It is performed by conducting repeated individual interviews with experts knowledgeable about the subject of the Delphi activity.  The steps of the process are (Mahmutovic, 2023):

1. Select participants: Select experts with knowledge about the topic/problem for which the decisions will be made.
   
2. Perform round-based surveys: Experts give their opinions on the selected topic each round based on a survey or questionnaire.
3. Aggregate and analyze survey responses:  The surveys/questions are revised each round based on results from the previous round. 
4. Continue rounds:  Survey rounds continue until a consensus is reached or a set stopping point is reached. There are typically at least three rounds before a decision is reached.   
5. Analyzing the decision results: The researcher identifies areas of agreement and disagreement, turns results into plans and opportunities for the future

One advantage of using the Delphi process is that the inputs are provided by experts.  The inputs are provided anonymously, so participants may provide more honest feedback.  Another disadvantage is that the participants aren’t brainstorming new ideas since they are responding to a questionnaire.  Also, since this method involves multiple rounds with the surveys being refined each round, the method may not be suitable when a decision needs to be made quickly.

The Nominal Group Technique (NGT) is a decision-making technique that collects input from group members to enable quick agreement on a solution.   Team members present their best ideas, and then the group discusses and prioritizes the suggestions.  The steps of the process are (ASQ, n.d.):

1. Problem statement:  The facilitator states the problem/topic and ensures understanding among the team members
2. Generation of ideas: Team members independently write down their ideas or solutions for the problem in a specified period (typically 5-10 minutes)
3. Share top ideas: Team members submit their best idea
4. Group discussion: The group discusses each idea and determines any edits, deletions, additions, or categorizations needed.
5. Voting and Ranking:  Rank the ideas using multi-voting or list reduction.   The solution with the top rank or the most points is selected. 

One advantage of the NGT is that it provides equal participation by obtaining inputs from each participant separately to reduce group interaction impacts.   It also is a good way to collect many ideas ensuring adequate coverage of the solution space (ASQ, 2023).  One disadvantage is that only one problem can be addressed at a time.   Other issues are that there is little flexibility in the process and inputs may not converge on a single decision. 

As an application example, either the Delphi or NGT method could be used to identify the best approach for communicating software process improvements to enable increased software compliance.  We would select participants from each of the stakeholder groups, specifically experts for the Delphi method, and develop a questionnaire based on the different compliance category types and communication forms.  Using the Delphi Methods, we would analyze the responses and refine the questions for the next round, repeating rounds until a solution is identified.  Using the NGT, we would ask each expert to provide their best answer for a given topic, refine and rank the solutions, and select the solution with the best score.

Comparing and Contrasting the Methods

Both methods rely on group inputs and evaluation of those inputs to arrive at a decision.  For both methods, it is possible to not reach a consensus. Differences in the methods are summarized in Table 1.

Table 1 Differences in Delphi and NGT Methods
Criteria	Delphi	NGT
Group member selection	Experts are selected.	The participants may not experts
Idea/solution candidates generated from	Anonymous survey/questionnaire responses re collected.	The participants provide ideas.
Identifying a solution	Multiple rounds of questions and responses are performed.	Voting and ranking is performed to identify the solution with the highest score.

 

References

ASQ (n.d.). About Nominal Group Technique. Learn About Quality. https://asq.org/quality-resources/nominal-group-technique

Mahmutovic, J. (2023, August 14). What is the Delphi Method and How Do You Use It in Surveys? SurveyLegend. https://www.surveylegend.com/research/what-is-the-delphi-method/#:~:text=5%20Steps%20of%20the%20Delphi%20Method%20in%20Research,5%205.%20Analyzing%20the%20Convergence%20of%20Opinions%20 Wade, W. (2012). Scenario planning: A field guide to the future. John Wiley & Sons.