Commentary on “Propagation of Uncertainty in Bayesian Diagnostic Test Interpretation”

Abstract

The work cited by the Nobel committee was done jointly with the late Amos Tversky during a long and unusually close collaboration. Together, we explored the psychology of intuitive beliefs and choices and examined their bounded rationality. This essay presents a current perspective on the three major topics of our joint work: heuristics of judgment, risky choice, and framing effects. In all three domains we studied intuitionsthoughts and preferences that come to mind quickly and without much reflection. I review the older research and some recent developments in light of two ideas that have become central to social-cognitive psychology in the intervening decades: the notion that thoughts differ in a dimension of accessibility -some come to mind much more easily than others -and the distinction between intuitive and deliberate thought processes.Section 1 distinguishes two generic modes of cognitive function: an intuitive mode in which judgments and decisions are made automatically and rapidly, and a controlled mode, which is deliberate and slower. Section 2 describes the factors that determine the relative accessibility of different judgments and responses. Section 3 explains framing effects in terms of differential salience and accessibility. Section 4 relates prospect theory to the general * This essay revisits problems that Amos Tversky and I studied together many years ago, and continued to discuss in a conversation that spanned several decades. The article is based on the Nobel lecture, which my daughter Lenore Shoham helped put together. It builds on an analysis of judgment heuristics that was developed in collaboration with Shane Frederick (Kahneman and Frederick, 2002 proposition that changes and differences are more accessible than absolute values. Section 5 reviews an attribute substitution model of heuristic judgment. Section 6 describes a particular family of heuristics, called prototype heuristics. Section 7 concludes with a review of the argument. INTUITION AND ACCESSIBILITYFrom its earliest days, the research that Tversky and I conducted was guided by the idea that intuitive judgments occupy a position -perhaps corresponding to evolutionary history -between the automatic operations of perception and the deliberate operations of reasoning. Our first joint article examined systematic errors in the casual statistical judgments of statistically sophisticated researchers (Tversky & Kahneman, 1971). Remarkably, the intuitive judgments of these experts did not conform to statistical principles with which they were thoroughly familiar. In particular, their intuitive statistical inferences and their estimates of statistical power showed a striking lack of sensitivity to the effects of sample size. We were impressed by the persistence of discrepancies between statistical intuition and statistical knowledge, which we observed both in ourselves and in our colleagues. We were also impressed by the fact that significant research decisions, such as the choice of sample size for an experiment, are routinely guide...