A kind of rational preference

Existing preference models are generally based on utility functions and study rational behaviors of humans. However human preferences are actually accompanied with irrational factors. Psychologists Tversky and Kahneman have given some examples that indicate humans are simply irrational by the standards of the utility axioms. How to depict some non-rational decision of human - that is, by what function this is done - is a crucial component of this subject of human (ir)rationality. In this paper, we apply filter and ultrafilter tools in nonstandard analysis to represent human preferences on two levels, intuitively and subconsciously. We indicate how this preference modeling using ultrafilter notion can reflect the combination of human rationality and irrationality. In particular, we show in what cases human preferences can be called non-rationality.