Expertise

Expertise consists of those characteristics, skills and knowledge of a person (that is, expert) or of a system, which distinguish experts from novices and less experienced people. In many domains there are objective measures of performance capable of distinguishing experts from novices:expert chess players will almost always win games against recreational chess players; expert medical specialists are more likely to diagnose a disease correctly and so on.

There are broadly two academic approaches to the understanding and study of expertise:
 * The first understands expertise as an emergent property of communities of practice. In this view expertise is socially constructed; tools for thinking and scripts for action are jointly constructed within social groups enabling that group jointly to define and accquire expertise in some domain.
 * In the second view expertise is a characteristic of individuals and is a consequence of the human capacity for extensive adaptation to physical and social environments. Many accounts of the development of expertise emphasise that it comes about though long periods of deliberate practice. In many domains of expertise estimates of 10 years experience or 10,000 hours deliberate practice are common.

Typically recent research on expertise emphasises the nurture side of the nature versus nurture argument.

Work on expert systems typically works from the premise that expertise is based on accquired repertoires of rules and frameworks for decision making which can be elicited as the basis for computer supported judgement and decision-making. However, there is increasing evidence that expertise does not work in this fashion. Rather, experts recognise situations based on experience of many prior situations. They are in consequence able to make rapid decisions in complex and dynamic situtions relying on recognition-primed decision-making.

In a critique of the expert systems literature, Dreyfus and Dreyfus suggest: "If one asks an expert for the rules he or she is using, one will, in effect, force the expert to regress to the level of a beginner and state the rules learned in school. Thus, instead of using rules he or she no longer remembers, as the knowledge engineers suppose, the expert is forced to remember rules he or she no longer uses. … No amount of rules and facts can capture the knowledge an expert has when he or she has stored experience of the actual outcomes of tens of thousands of situations.”"

An important feature of expert performance seems to be the way in which experts are able to rapidly retrieve complex configurations of information from long term memory. They recognise situations because they have meaning. It is perhaps this central concern with meaning and how it attaches to situations which provides an important link between the individual and social approaches to the development of expertise.

In line with the socially constructed view of expertise, expertise can also be understood a form of power; that is, experts have the ability to influence others as a result of their defined social status. Dreyfus, H. and Dreyfus, S. (2005) Expertise in real world contexts, Organization Studies, 26(5), 779-792.

Anders Ericsson, Charness. Feltovich, and Hoffman(2006)'The Cambridge Handbook of Expertise and Expert Performance' Cambridge: Cambridge University Press.