theory, the model of a rational decision maker–the *rational economic man* paradigm[^2]–can be described as follows (based on a definition by Rubinstein [@rubinstein1998modeling p. 7 et sqq.])[^3].

\[clear-pref\] Given a set of choice options $A$, the rational economic man determines his choice of elements $A^{*} \subset A$ according to his preference order (partial order) $\succeq$ so that $\forall A' \in 2^A: A^{*} \succeq A'$; *i.e.*, $A^{*}$ is the rational man’s preferred option when compared to all possible alternatives.

For example, given the choice set $\{coffee, snack\}$, the rational man’s preferred option could be $\{coffee, snack\}$, given he chooses this element from the set $2^{\{coffee, snack\}}$. The choice implies $\forall A' \in \{ \{ coffee \}, \{ snack \}, \{ \} \}: \{coffee, snack\} \succeq A'$, as depicted in Figure \[fig:lattice-prefs\].

(All) at(1.5,4) [$\{c, s\}$]{}; (Coffee) at(0,2) [$\{c\}$]{}; (Snack) at(3,2) [$\{s\}$]{}; (None) at(1.5,0) [$\{\}$]{}; (All) edge node\[left\] (None); (All) edge node\[left\] (Coffee); (All) edge node\[left\] (Snack);

In the context of this paper, an important property of the rational man’s choice process is *reference independence*.

\[ref-in\] Given a set of choice options $A$ and any two possible subsets of choice options $A_1 \subseteq A$ and $A_2 \subseteq A$, with $A_1 \subseteq A_2$ 