EXPERT AND NOVICE PERFORMANCE IN BIOCHEMISTRY PROBLEM-SOLVING AND EXPLANATION (CAUSAL, STRATEGIES, SCIENTIFIC, DECOMPOSITION

Previous research on scientific problem solving suggests that experts and novices employ different problem solving strategies. Most of this prior work has focused on areas which are well-organized around mathematical principles. This dissertation investigates expert and novice problem-solving performance in biochemistry, a scientific area that is not as mathematically organized and contains many terms and specific facts. The primary goal of this study is to determine the strategies that experts and novices use in solving problems and in explaining the solutions. This primary goal requires a methodology which can move from the data of the verbal protocols to an identification of the subject's problem-solving strategies in a knowledge-rich domain.;The study employed two problems involving abnormal biochemical function. Subjects were required to provide an account of how this abnormal function could be brought about. Four expert biochemists and eight medical students were given one of the two problems. After solving the problem, each subject gave an explanation of the biochemical phenomenon that had led to the abnormal function.;This study found that experts in biochemistry reasoned using two different types of problem decompositions; one beginning with normal function, the other with a known pathology. However, novices reasoned using only the normal function problem decomposition. Furthermore, experts used these strategies to consider more alternatives than novices, and often tended to reach a final answer more slowly.;Analysis of the explanations following problem solving demonstrated that experts used a form of the normal function problem decomposition, which was more general than in the problem solving protocols. Novices did not reorganize the information in their explanations along the lines of general principles.;This study suggests that, unlike experts in previously-studied domains, experts in biochemistry are more likely to use a problem decomposition, and do not reach the correct answer as quickly as novices.