3. DECISION THEORY AND STAKEHOLDER DECISION ANALYSIS
3.3. Conclusion on Adaptable MCDA Techniques in Solving the Research Problem
After the review of relevant literature, the need to answer the research questions in Section 2.3.2 and achieve the research objectives, this research considers:
That MCDA has been employed in solving fire safety-related problems but was limited to fewer decision attributes, single decision-making scenarios, potential stakeholder skewed judgements and unresolved design decision uncertainties (see Section 3.1.1.2). Hence, this research project is carried out to extend the knowledge in applying decision analysis and stakeholder decision-making process in the fire safety engineering discipline i.e. to improve on the shortcomings of previous scholarly works as discussed in Section 3.1.1.1. To realise this, the research team considered as valuable: firstly, test the stakeholder decision-making process/tools on a general case study of steel framed buildings using larger data from multiple stakeholder views to understand their adaptability strengths and limitations in a group decision-making. Then develop an adaptable technique and narrow the process/technique to a specific case study using a virtual building. Therefore, this influences
the broad research space/research title to cover the investigations to be achieved in the project. This research decision is without prejudice that human beings can be unconsciously biased to specific decision attributes, preferences or vested interests in particular technologies/suppliers. However, the essence of MCDA techniques is to capture these varying views or interests based on the intensity of the participant-experts’ feeling, normalise and prioritise these views to show the criteria importance levels which may be revised for synthesis and ranking. Stakeholder judgement sensitivities can be tested as well to improve the process
The Analytical Hierarchy and Network Processes (AHP and ANP) provides the platform or goal-rating structure on which fire design stakeholder goals/views/opinions can be identified and extracted. This is premised on the fact that AHP/ANP have “trademark” structured questions for the decision-maker/s that put the decision goal, criteria and competing options in practical contexts and perspectives, unlike PROMETHEE and TOPSIS. The decision- maker/s views, judgements, and ratings are traditionally entered as numbers or elements in a judgement matrix, following a reciprocal fundamental scale. Hence, the AHP/ANP questions, reciprocal scale, and matrices can be easily used to develop a questionnaire or goal-rating document to engage fire design stakeholders.
The application of group multi-criteria decision analysis is considered to analyse fire design stakeholder views toward balancing their goals for suitable design decision-making. The adopted techniques for further investigation and application include Geometric Mean Method-Analytic Hierarchy Process (GMM-AHP); Weighted/Geometric Mean Method- Analytic Network Process (WGMM-ANP). The GMM-AHP and W/GMM-ANP are adopted to address the shortcomings of other AHP applications in fire safety research discussed in Section 3.1.1.2. These shortcomings include accounting for scenarios of multiple decision- makers’ judgements, managing outright dominance of a decision criterion. The aggregation of individual stakeholder judgements using W/GMM can potentially manage multiple stakeholder views, while the AHP-synthesis in distributive and ideal modes can potentially
address performance and dominance of decision criteria (AHP-Step 5).
AHP in comparison with the WSM, WPM, PROMETHEE-1 MCDA techniques typically considers the analysis of both benefits and costs attributes of a decision problem qualitatively and quantitatively. This is suitable for application in this research project because the structural fire design decision-making process may consider costs decision criteria such as
constructability, financial risk management, and benefits decision criteria such as building aesthetics, structural fire resistance, etc. AHP also provides a logical and reciprocal pairwise comparison rating scale to support both single and group judgements (i.e. GMM) on decision elements; it uses transparent criteria weighting procedure and synthesis toward complete ranking of the competing options and allows consistency checks of stakeholder judgements. The Analytic Network Process (ANP) is a generalisation and extension of AHP whereby possible interactions or influences between dependent and interdependent decision attributes in complex decision problems can be assessed. Therefore, ANP is built on the concept of ‘influence’ to give decision-maker/s the opportunity to go beyond the top-down AHP- approach in decision-making processes. Given that it is the state-of-the-art MCDA technique built on the AHP, it is considered here to account for possible interdependencies among steel structural fire design decision criteria which may not be feasibly achieved using other MCDA techniques.
The use of TOPSIS in many cases will depend on data generated from application of other risk or decision analysis techniques to complete the initial decision matrix. However, its procedure of synthesis whereby multidimensionality is managed through normalisation and its seamless analysis of both qualitative and quantitative conflicting decision attributes sets it up as a suitable ranking tool. Hence, the application of TOPSIS in this research is best considered as a component of a hybrid MCDA technique that integrates, Geometric Mean Method (GMM) + Analytic Hierarchy Process (AHP) + Technique for Order of Preference by Similarity to Ideal Solutions (TOPSIS), with the acronym, GAT. Importantly, GAT is potentially the hybrid decision analysis technique considered for development as a key deliverable of this research project, which depends on successful investigation and application of its adjoining components.
The considered MCDA techniques are geared toward achieving the clearest identification of fire design stakeholder goals, analysis of stakeholder views as well as ranking the competing steel structural fire protection options. The ranked options are expected to show stakeholder preferred options in protecting steel structures in fire. However, further evaluation may be needed to critically assess the ranked options due to the statistical significance of participant- stakeholders regarding data skewness. In many practical scenarios, most stakeholders may lean toward specific decision criteria, thereby causing a skewed overall decision, which may require optimisation.
The following chapters will investigate AHP through a pilot study, apply GMM+AHP and W/GMM+ANP to extract individual judgements of real fire design stakeholders and integrate quantitative structural fire analysis and fire protection options’ costs using GAT to balance or optimise stakeholders design decision-making.