Academic journal article Psychonomic Bulletin & Review

Evidence Accumulation in Decision Making: Unifying the "Take the Best" and the "Rational" Models

Academic journal article Psychonomic Bulletin & Review

Evidence Accumulation in Decision Making: Unifying the "Take the Best" and the "Rational" Models

Article excerpt

An evidence accumulation model of forced-choice decision making is proposed to unify the fast and frugal take the best (TTB) model and the alternative rational (RAT) model with which it is usually contrasted. The basic idea is to treat the TTB model as a sequential-sampling process that terminates as soon as any evidence in favor of a decision is found and the rational approach as a sequential-sampling process that terminates only when all available information has been assessed. The unified TTB and RAT models were tested in an experiment in which participants learned to make correct judgments for a set of real-world stimuli on the basis of feedback, and were then asked to make additional judgments without feedback for cases in which the TTB and the rational models made different predictions. The results show that, in both experiments, there was strong intraparticipant consistency in the use of either the TTB or the rational model but large interparticipant differences in which model was used. The unified model is shown to be able to capture the differences in decision making across participants in an interpretable way and is preferred by the minimum description length model selection criterion.

A simple but pervasive type of decision requires choosing which of two alternatives has the greater (or the lesser) value on some variable of interest. Examples of these forced-choice decisions range from the everyday (e.g., deciding whether a red or a green curry will taste better for lunch), to the moderately important (e.g., deciding whether Madrid or Rome will provide the more enjoyable holiday), to the very important (e.g., deciding whether cutting the red or the black wire is more likely to lead to the destruction of the world).

The Rational Approach

One approach to modeling the way people make these decisions, often referred to as the rational approach, assumes that all of the relevant available information is combined in some (near) optimal way. At lunchtime, this means that knowledge of the ingredients of the different curries, previous experiences with the two curry types, current sensory information about the available curries, and a range of other relevant information must be weighed and combined to give an overall preference. Simon ( 1976) described this approach as substantively rational, because its overarching goal is to maximize the utility of the decision made, regardless of the efficiency of the processes required to make the decision. This rational approach is often viewed as a normative theory of decision making and is central to the decision and utility theoretic frameworks widely used in the physical sciences and in the behavioral sciences, such as psychology and economics (see Doyle, 1999, for an overview).

A large number of well-known and successful models in cognitive psychology aim for substantive rationality. For example, the MINERVA 2 model of memory retrieval (Hintzman, 1984) uses the sum of every memory trace, weighted by the frequency of each trace, to remember or reconstruct stimuli. Similarly, the ALCOVE model of category learning (Kruschke, 1992) makes categorization decisions by potentially considering the weighted sum of evidence for each category alternative provided by every stimulus in a domain, and the same is true of the closely theoretically related context model (Medin & Schaffer, 1978) and generalized context model (Nosofsky, 1984). There are also various Bayesian cognitive models, including accounts of generalization (Myung & Shepard, 1996; Shepard, 1987) and concept learning (Tenenbaum, 1999; Tenenbaum & Griffiths, 2001), that integrate across prior-weighted probability densities to determine response probabilities and, so, strive for substantive rationality in a very direct way. Finally, there are substantively rational psychological models-most notably, Anderson's (1990, 1991, 1992) rational modelthat introduce time and memory constraints into the criteria for decision making but continue to allow for the weighting and combination of all of the relevant available evidence to optimize decisions under these criteria. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed

Oops!

An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.