A theory of reference dependent behavior

There is extensive field and experimental evidence in a wide variety of environments showing that behavior depends on a reference point. This paper provides an axiomatic characterization for such behavior. Our approach is dual, we study choice behavior and preference relations. We proceed by gradually imposing more structure on behavior, requiring higher levels of rationality, that free the decision-maker from certain types of manipulations. Depending on the phenomena one wants to model, one degree of behavioral structure will be appropriate or another. We provide two applications of the theory: one to model the status-quo bias, and another to model addictive behavior.The authors gratefully acknowledge financial support by the Spanish Commission of Science and Technology (CICYT, SEC2003-08105)