In many domains, experts produce complex products such as texts on a given
topic or performances of a given piece of music. Although judges can reliably
assess the superior quality of the product, it is difficult to analyze such prod-
ucts in order to identify the measurable aspects capturing the superior quality
of the product. Hence, in their analysis of expertise in writing, Scardamalia and
Bereiter (1991) focus on systematic characteristics of the cognitive processes
involved in designing and writing a text in an effort to differentiate expert from
novice writers.
It is, of course, possible to give up the hope of designing a collection of tasks
that could capture the full extent of the superior performance and focus instead
on one or more well-defined activities involved in the expertise or measur-
ingknowledgeaboutthetaskdomain.Inadoptingsuchanapproach,oneno
longer can be certain that one is examining cognitive structures and processes
essential to the superior performance. Occasionally, expected differences be-
tween the performance of novices and that of experts in component activities
are not found. For example, Lewis (1981) found no reliable differences in per-
formance on algebra problems between expert mathematicians and the top
third of a group of college students. The most frequently studied activity re-
lated to expert performance is memory for meaningful stimuli from the task
domain.
Tasks Focusing on Domain-Specific Memory Performance. In the context of the
difficulties of identifying a collection of tasks that can capture the expertise, it is
easy to see the attractiveness of studying memory performance. It is possible to
evaluate memory performance for presented information by means of recogni-
tion and reproduction of literal details (e.g., correct placement of chess pieces),
which does not involve any in-depth analysis of tasks or prior knowledge in
the given domain. Large samples of different meaningful stimuli can relatively
easily be extracted from a given domain even though no formal description of
the corresponding population of stimuli is given. Similarly, it is relatively easy
to assemble unrepresentative or even meaningless stimuli by recombining
stimulus elements in an arbitrary or random manner.
In a wide range of different domains, experts have been shown to display
superior memory performance for representative stimuli from their domains
of expertise when adaptations of Chase and Simon’s (1973) original procedure
have been used: chess (for a review, see Charness, 1991); bridge (Charness,
1979; Engle & Bukstel, 1978); go (Reitman, 1976); music notation (Sloboda,
1976); electronic circuit diagrams (Egan & Schwartz, 1979); computer pro-
gramming (McKeithen, Reitman, Rueter, & Hirtle, 1981); dance, basketball, and
field hockey (Allard & Starkes, 1991). Other studies have shown superior re-
tention of domain-related information as a function of the subject’s amount of
knowledge of the domain, such as baseball (Chiesi, Spilich, & Voss, 1979; Spi-
lich, Vesonder, Chiesi, & Voss, 1979; Voss, Vesonder, & Spilich, 1980) or soccer
(Morris, Gruneberg, Sykes, & Merrick, 1981; Morris, Tweedy, & Gruneberg,
1985). Hence, many studies have found evidence supporting a monotonic rela-
tion between recall performance for a domain and expertise in that domain.
There are, however, several lines of research that have questioned the general-
ity of that relation. Sloboda (1991) points out the striking similarity in accuracy
530 K. Anders Ericsson and Jacqui Smith