Essays in normative and desriptive decision theory.

Summary The field of decision theory has been very active since von Neumann Morgenstern 1943. New decision models have revolutionized the way we can analyze our actions and decisions. However, Allais' paradox in 1953 forced theorists to clarify the purpose of their models. This evolution allowed the discipline to define clear and solid methods of empirical validation of its descriptive approach. However, in contrast, normative decision theory is still struggling to determine an objective and constructive methodology to settle its internal debates about the rationality of decision-theoretic models. Providing such a methodology is the main objective of this thesis.