Psychological heuristics are formal models for making decisions that (i) rely on core psychological capacities (e.g., recognizing patterns or recalling information from memory), (ii) do not necessarily use all available information, and process the information they use by simple computations (e.g., ordinal comparisons or un-weighted sums), and (iii) are easy to understand, apply and explain. The contribution of this article is fourfold: First, the conceptual foundation of the psychological heuristics research program is provided, along with a discussion of its relationship to soft and hard OR. Second, empirical evidence and theoretical analyses are presented on the conditions under which psychological heuristics perform on par with or even better than more complex standard models in decision problems such as multi-attribute choice, classification, and forecasting, and in domains as varied as health, economics and management. Third, we demonstrate the application of the psychological heuristics approach to the problem of reducing civilian casualties in military stability operations. Finally, we discuss the role that psychological heuristics can play in OR theory and practice. 
On the role of psychological heuristics in operational research; and a demonstration in military stability operations