Hmm... fast and frugal 'reflection' ?

In reply to David Hardman's comment on my thoughts about the heuristics and biases paradigm and the current approach to the whole of psychology, I went back and read Dhami's (2003) write up of the bail decision study, trying to keep a more objective stance. It seems that I had made some unfounded assumptions at the first place, which warrant further attention to my own reflective processes (more on this later). To begin with I failed to see Dhami's findings in their particular context. That is, the paper discussed bail decision and not jury or juror decision making processes. There is certainly a qualitative difference between a bail or jail decision by a magistrate, pending later trial, and later stage legal decision making. The pescriptive validity of fast and frugal heuristic (at least in the context described in the study discussed here) is evident. Nonetheless, what is the importance of judgemental accuracy of such heuristics if people don't actually use them? There is nothing to suggest that we can be certain that people actually use such heuristics in general or exclusively, and even if they do under certain circumstances (i.e. time constraints) it seemes dubious to generalise.

To stay within the context of decision making in courts, consider the widely popularised R v Maxwell case. In January 1996, Maxwell bros were cleared of all charges to defraud pension funds of £400 million, against the weight of evidence and public opinion. This case is a prime example of a 'perverse acquittal', i.e. a jury decision that goes against public opinion and what the evidence suggests. Surely, jury decision making is a group process and as such different than individual decision making discussed here, but leaving group dynamics or conformity etc, aside, it would be reasonable to suggest that individual jurors 'world knowledge', i.e. their beliefs about 'how things are' may have their role in such cases and some form of cognitive architectural equation would be unlikely to predict the outcome in such cases. Thus, jurors may as well employ heuristics but a judgement may also be influenced by individual differences and by the use of one's own world knowledge. Enquiring into the phenomena of consciousness, by asking people what they think while judging, or, from a more quantitative point of view, measuring attitudes and biases by using scales and questionnaires would also elucidate aspects of judgement other than heuristics.

Therefore one's world knowledge may affect one's decision/behaviour/judgement, and particularly on my own world knowledge, this is exactly what happened when I wrote the previous post. That is, the way I see the world, and thus the way I see psychology, cognitive psychology and research methodology caused me to adopt a somewhat close-minded attitude, when reading about the role of heuristics in human judgement. On second thought, heuristics seem to be part of the picture and as such give a better insight to phenomena of decision making (even though I still don't see how a mathematical equation could address the complexity of judgement and not miss exceptional cases and more subjective aspects). It is important not to see things as mutually exclusive and to return to my previous post, both quantitative and qualitative methodologies seem to have their own strengths and limitations but could perhaps be used to describe different aspects of reasoning.


Dhami, M. K. (2003). Psychological models of professional decision-making. Psychological Science, 14, 175-180.