Knowledge and Performance: Tracking the Development of Expertise

Abstract

Performance in complex tasks may not be a monotonic function of experience. In several domains, an inverted U-shaped function has been observed, with increased error rates being associated with intermediate levels of experience. This contradicts the idea of a linear relationship between the development of expertise and performance levels. A simple monotonic increase in similarity to some ideal knowledge representation may not adequately describe changes in knowledge over time. Crosssectional research on people with varying levels of expertise at complex tasks supports the idea of distinct stages in the development of expertise and helps account for an increase in errors as people develop new skills.We conducted a longitudinal study of ninth-grade biology students' understanding of certain ecology concepts. Students' mental representations of these concepts were measured three times during a 12-week course. Over the semester, similarity to the knowledge representation of a good student was more predictive of final grades than was similarity to the teachers' expert representation, as was predicted. According to the non-monotonic theory of knowledge development, expert representations are less powerful predictors of student performance because they do not adequately model student knowledge of the domain. These data support the non-monotonic theory of knowledge development by revealing the superiority of the good student representation over the teacher representation.

Relating indices of knowledge structure coherence and accuracy to skill-based performance: Is there utility in using a combination of indices?

“…To date, few studies have examined the usefulness of either number of links or coherence. Number of links has been used to show qualitative changes during training (e.g., Rowe, Miller, Dibble, & Steuck, 1995). To our knowledge, previous studies have not examined the extent to which the number of links in knowledge structures is correlated with skill-based performance.…”