Strategic Multi-criteria Decision-Making Against Pandemics Using Picture and Spherical Fuzzy AHP and TOPSIS

With the coronavirus that emerged suddenly and affected the masses, it became clear how unprepared we were for the pandemic situation both individually and at the state level. Over the past period, many different transmission prevention strategies have been implemented in different countries, and their results have been observed. Unfortunately, a complete preventive strategy has not yet been developed, and the disease continues to spread. There is a long and arduous process ahead of us in the fight against coronavirus. In order to better manage this process, this study aims to compare the strategic decisions to be taken by the states, especially during the periods when the disease spreads. The intervention strategies have a strong impact on economics, social life, health systems, and environment. As a result of intervention methods, the income of individuals, health sector, tourism sector and companies are affected economically. Yet, modeling strategic decisions under pandemic conditions is complicated since multiple factors should be considered. The uncertainties and imprecision in the evaluation process increase the complexity of the decision-making process. In this study, the decision-making procedure criteria are defined using multi-criteria decision-making methods, and the alternative strategies are compared using TOPSIS method. Picture fuzzy sets and spherical fuzzy sets are used to handle uncertainty in the decision-making process, and the results are compared. These two methods are compared based on the results and the applicability.