In this study, four different approaches to the prioritization concept of expert opinions, which is frequently used in multi-criteria decision making methods, are applied to the improved fuzzy analytical hierarchy process method. In those studies which depend on the questionnaires, it is commonly asked that who these experts are, whether they are fully acquainted with the subject, and what their education level and experience status are. In the literature, there exist four different approaches to determine the expertise coefficients: (1) the year based career, age or experience. (2) graduation, education and experience in the sector. (3) using consistency coefficient of a judgment matrix as a coefficient of expertise, and (4) determination of expertise according to the questions in the questionnaire. In this study, each approach is analyzed, and embedded into the improved fuzzy analytical hierarchy process method. As a result, it is shown that all the data regarding to expertise of experts in decision making problems that is based on expert judgments can be transferred to the decision making method. It is observed that the expert coefficients and the moderator's assignments on the decision matrix definitely affect the final weights and rankings of the criteria and alternatives, and can change the results in a huge amount.