Monotone threshold representations

Motivated by the literature on ``choice overload'', we study a boundedly rational agent whose choice behavior admits a \textit{monotone threshold representation}: There is an underlying rational benchmark, corresponding to maximization of a utility function $v$, from which the agent's choices depart in a menu-dependent manner. The severity of the departure is quantified by a threshold map $\delta$, which is monotone with respect to set inclusion. We derive an axiomatic characterization of the model, extending familiar characterizations of rational choice. We classify monotone threshold representations as a special case of Simon's theory of ``satisficing'', but as strictly more general than both Tyson's (2008) ``expansive satisficing'' model as well as Fishburn (1975) and Luce's (1956) model of choice behavior generated by a semiorder. We axiomatically characterize the difference, providing novel foundations for these models.