Simultaneous decision-making: An overview of theories and research results

The aim of this paper is to review empirical findings and explanations relevant to the issue when concurrent decisions are integrated and when they are not integrated. There are few directly related studies. Therefore, the review also covers related phenomena involving the effect of a prior outcome on subsequent decisions, sunk-cost effects, and escalation. An important question emerging from the literature review is the question why integration have been obtained in studies of effects of prior outcomes, sunk cost effects, and escalation, at the same time as this has not been the case with concurrent decisions? One reason may be the existence of mental accounting in these studies. Another is that choices are riskless. An idea for further research is to make subjects being able to think through all possible consequences in a concurrent decision problem. By explicitly illuminating the risk or uncertainty to the subjects, it may be possible to obtain integration in concurrent decisions.