Abstract
We consider the existence problem of errors in decision making processes under risk from a set-theoretical perspective. Choice adjustment errors have been identified but never formalized by the experimental economics/decision theory literature. We show that choice adjustment errors can be naturally derived from gaps in the range of the utility functions of decision makers. Introducing the concept of “error-induced certainty equivalent”, we account for the intrinsic generation of error approximations in any decision making process under risk. Finally, the existence problem of minimal error functions is shown to be equivalent to that of determining best approximations to the expected utility values defined by the corresponding decision processes.