The determination of weights in decision-making problems can be deduced as a complex process of preference formation. Preferences are expressions of behavioral attitudes and are affected by external circumstances, such as risk and ambiguity. The objective of this research is to examine the impact of both the human factor and the weighting methods on the weighting process in decision-making problems. Based on relevant literature a new methodology is proposed and applied to identify with the use of a psychometric function the behavioral attitudes of decision-making analysts against risk and ambiguity. Furthermore, the examination of process-related features such as the weighting method, the weighting scale and the weighting problem's presentation provides additional knowledge on the understanding of the weighting process in decision-making problems. Thus, an original survey is designed, aiming at: a) the identification of the respondents' attitudinal preferences based on multiple personality tests and b) the elicitation of weight assignments through the use of different weighting tasks and subtasks. The findings reveal that the weightings and their consistency are significantly affected by the elicitation method, the nature of the weighting scale and the problem's framing. It is also interesting that the decision analysts' behavioral traits, in association with the problem's methodological aspects, affect the weight assignments, thus providing evidence for the potential to predict weightings in the decision making process.