The representation of physics problems in relation to the organization of physics knowledge is investigated in experts and novices. Four experiments examine the existence of problem categories as a basis for representation; differences in the categories used by experts and novices; differences in the knowledge associated with the categories; and features in the problems that contribute to problem categorization and representation. Results from sorting tasks and protocols reveal that experts and novices begin their problem representations with specifiably different problem categories, (...) and completion of the representations depends on the knowledge associated with the categories. For, the experts initially abstract physics principles to approach and solve a problem representation, whereas novices base their representation and approaches on the problem's literal features. (shrink)

In this article, the pragma-dialectical model of a critical discussion is demonstrated to provide a useful instrument for discovering causes of an unsatisfactory development of problem-solving discussions. First a sketch is given of the development of a problem-solving discussion which, in the opinion of the participants themselves, developed in an unsatisfactory fashion. Then it is argued that this development can be traced back to flaws in the execution of the stages of a critical discussion.

The present study tested the existence of a cognitive schema that guides people's evaluations of the likelihood that observed problem-solving processes will succeed. The hypothesised schema consisted of attributes that were found to distinguish between retrospective case reports of successful and unsuccessful real world problem solving (Lipshitz & Bar Ilan, 1996). Participants were asked to evaluate the likelihood of success of identical cases of problem solving that differed in the presence or absence of diagnosis, the selection of appropriate or inappropriate (...) solutions, and the pairing of diagnosis with appropriate or non-appropriate solutions. Consistent with the proposition, diagnosis affected perceived likelihood of success, albeit only when solution quality was held constant, and appropriate diagnosis with a compatible solution produced higher perceived likelihood of success than appropriate diagnosis with incompatible solutions. In addition, results showed that solution quality played a significant role, and that compatibility with a six-phase rational model of problem solving played no role in judging likelihood of success. (shrink)