Fuzzy cognitive maps and neutrosophic cognitive maps analysis of the emergence of COVID-19 post-vaccination / Nurul Eylia Maisarah Mazlan and Nur Amani Izzati Mohd Azhan

After several years of the spread of coronavirus disease 2019 (COVID-19) around the world occurred World Health Organization (WHO) has stimulated great efforts to develop a vaccine against the COVID-19. Therefore, all of citizen is obliged to take the vaccine for precaution. However, the vaccine is only one step to reduce the spread of COVID-19, where the appearance of COVID-19 can occur after vaccination. Some of people do not understand the vaccine function where it is used to prevent spreading COVID-19. This research is analysed the emergence of COVID-19 post-vaccination by using the method of Fuzzy Cognitive Maps (FCMs) and Neutrosophic Cognitive Maps (NCMs). Both methods are suitable to apply in medical diagnosis since it involves uncertainty and indeterminacy. These methods of FCMs and NCMs involved eight steps included with the step of comparison to achieve the objectives. The collected data from an interview with two experts called as a concept and from there the directed graph and adjacency matrix are constructed. Multiplication between vectors and matrices are repeated until the fixed point in finding the hidden pattern for all the concepts for COVID-19 post-vaccination obtained. The results obtained by the first expert for both methods gives four different results with different value in limit cycle but method of NCMs gives better in analysis of the emergence of COVID-19 post- vaccination because it was found that there is an indeterminant factor in NCMs which is the concept of C4 where people having high blood pressure, diabetes, tuberculosis, elder people who are violating C3. The both methods of FCMs and NCMs in second expert showed the same result which is ‘1’ shows the persons having all the factor are have the possibility and high risk of getting COVID-19. The method of NCMs cannot applied in second expert’s data since it did not show the relation of indeterminacy between two concepts.