In over twenty five years of research, Ullman has developed what he calls “Decision Thinking”. It is based on his research that began in the late 1980s when he explored the question – how do engineers and designers make product development decisions. What made his work unique is that he approached it as an engineer, with the aim of understanding decision making sufficiently to develop practical and applicable methods and tools.
Decision thinking forces addressing decision making under uncertainty as uncertainty is a part of all decisions. Decision thinking forces addressing multiple stakeholders as their values may differ and their knowledge is, at the same time, additive and conflicting.
Decision thinking suggests that looking at design or business problem solving as decision-making is a useful approach to understanding problems and generating a good solutions to them. This view is supported by extensive literature from psychology, sociology, decision theoretics, business and engineering. Further, based on Ullman’s research and supported by the literature there are sixteen characteristics of ideal decision making. For more on these sixteen and how five existing decision support methods compare to the ideal click here for the white paper, The Ideal Engineering Decision Support System.
In a recent, published paper (INCOSE’s Insight, July 2012) Ullman further delved into Decision Thinking as applied to systems design. From the Decision Thinking view, system design is the evolution of information punctuated by decisions, decisions that are based on uncertain and evolving estimates from agents, web searches, simulations, tests, experience, or wild guesses; all tempered by conflicting human values, estimates and beliefs. The uncertainty creates risks with every decision made, regardless of whether the decision is focused on the architecture of the system, the relationships of the sub-systems, or the configuration of code, parts and assemblies in the sub-systems. These thoughts are further developed in the paper, Decisions of the 3rd Kind.
Many details on decision thinking are in the book Making Robust Decisions written by Ullman in 2006.