How do you use the Delphi method for project estimation?

The Delphi method for project estimation involves gathering expert opinions through multiple rounds of anonymous surveys. Each round refines estimates based on feedback and statistical analysis. This iterative process continues until a consensus is reached, providing a reliable estimate.

The Delphi method is a forecasting and estimation technique where a group of experts anonymously provide feedback on specific questions related to a project or decision. Through iterative rounds, experts can adjust their opinions based on the group’s responses, which helps to refine estimates and predictions in areas where data is uncertain or incomplete.

- Identify experts: Select a diverse group with relevant experience. - Initial survey: Collect independent estimates for project parameters (cost, time, etc.). - Summarize responses: Provide a summary of estimates, including range and average. - Second round: Experts revise their estimates based on the summary. - Repeat rounds: Continue until estimates converge. - Final estimate: Reach a consensus on the most accurate project estimate. - Documentation: Record assumptions and final estimates for future reference.

In software the Delphi method is used rarely. First, because you need a group of almost equal experts in respect of their experience and skills. In other words, several full-stack developers. All should understand how to fulfil the task and evaluate it accordingly. Until there is no the consensus, the rounds of anonymous estimation will take place. So the main hurdle is to find at least 3-4 experts. Full-stacks are usually totally engaged in development. So they need an extra time for estimation. Actually, traditional poker for story mapping is Delphi method with the constraint that all devs have the same tech stack.

O método Delphi é uma técnica de previs?o e tomada de decis?o em grupo que busca alcan?ar consenso entre especialistas por meio de um processo estruturado de várias rodadas de questionários. Ele foi desenvolvido nos anos 1950 pela RAND Corporation e é amplamente utilizado em áreas como negócios, educa??o, saúde e ciências sociais.

In my experience, I have used the Delphi method a few times for various purposes: identifying risks, estimating durations or efforts, ordering a list of options on which I wanted the preferences of a panel of participants and things of this type. It is a very valid method because with 2 or 3 rounds you reach a good degree of consensus but what I would suggest is to guarantee that there is anonymity. Let me explain, each participant must not know who are the other members of the panel that you have selected and involved in the method because otherwise antipathies, sympathies, biases and roles condition the participants. Finally, it is good to formulate the question well and clearly because otherwise you will have distorted answers.

To apply the Delphi method in project estimation, follow these steps: - Select the experts - First round of questions: Send out a set of questions to the experts to gather their initial estimates or opinions on key aspects of the project (e.g., time, cost, resources required). - Analyze and summarize responses: Collect the feedback and identify any areas of disagreement or uncertainty. - Second round of questions: Share a summary of the responses and allow the experts to adjust their estimates based on the feedback from others. - Repeat the process: Continue the rounds until the experts converge on a consensus or acceptable range of estimates, typically requiring 2-3 rounds.

Eu costumo seguir esses passos: 1) Determinar o que você deseja estimar sobre o projeto. 2) Escolher os especialistas com experiência diversificada e relevante ao projeto. 3) Criar um questionário com espa?o para comentários adicionais dos especialistas. 4) Coletar as respostas de forma an?nima. 5) Compartilhar um resumo das estimativas e análises da primeira rodada, permitindo que os especialistas revisem suas próprias respostas à luz das estimativas agregadas do grupo e depois repetir o processo até chegar a uma convergência.

Here you are the main benefits (in my opinion) 1. Improved estimation accuracy: The iterative feedback process refines estimates, reducing bias and leading to more accurate project timelines and costs. 2. Early risk identification: Engaging diverse experts helps identify potential risks early, allowing for proactive mitigation. 3. Facilitating consensus: The Delphi method helps achieve consensus on critical estimates, minimizing misunderstandings in project execution. 4. Managing uncertainty: It handles uncertainty by converging on a range of acceptable estimates, even with limited data.

The Delphi method provides several advantages in project estimation: - Collective expertise: By gathering insights from multiple experts, the method ensures a more comprehensive and informed estimation process. - Handling uncertainty: It is particularly useful in situations where there is limited data, as it helps generate estimates through expert judgment rather than relying solely on historical data. - Anonymity: Experts can provide their opinions without fear of judgment or group pressure, leading to more honest and diverse responses. - Flexibility: The method can be applied in complex, evolving projects where multiple perspectives are valuable for making accurate predictions.

Despite its strengths, the Delphi method also has some limitations: - Time-consuming: The iterative rounds can take significant time, especially in large-scale projects, delaying the final consensus. - Relies on expert judgment: The quality of the estimates is dependent on the expertise and experience of the selected participants. Poor selection of experts can lead to unreliable results. - Difficulty in achieving consensus: In some cases, experts may continue to hold divergent views, making it challenging to reach an agreement and affecting the final estimate. - Lack of direct interaction: The absence of face-to-face interaction can limit the depth of discussion, which might otherwise lead to richer insights and deeper understanding.

- Expert selection: Experts should not only have technical knowledge but also practical experience in the project’s context. - Question design: The clarity and relevance of the questions asked during the rounds significantly impact the quality of the feedback received. - Technology support - Integration with other estimation techniques: Combining the Delphi method with other approaches can enhance the reliability and accuracy of project estimates. - Managing group dynamics: Although experts are anonymous, the facilitator must still manage the group’s dynamics to avoid groupthink or overly dominant opinions that could skew the results.

The Delphi method for project estimation involves iteratively polling a panel of experts anonymously to converge on consensus estimates. In renewable energy projects like subsea/offshore wind power, grid code compliance studies, manufacturing, and battery energy storage, Delphi can refine cost, timeline, and risk assessments. For instance, experts assess factors like equipment costs, installation challenges, regulatory hurdles, and technology advancements to forecast project parameters accurately.