Xavier de Viviés
How does a subject build a representation of the problem that he or she is solving ? One hundred and sixty-two participants solved problems (isomorphs of the Tower of Hanoï problem) that had been constructed manipulating (a) the semantic and computational context in which the change of state is presented (nature of the context) ; and (b) the number of physical cues that the subject applied when representing the problem (rule representation). The results showed that each of these factors had an effect on general performance. However, the observation of different types of dependant variables shows different effects : the nature of the context affected the time that a person spent between one state and the following one ; the type of rule representation affected the number of steps necessary to solve the problem, as well as the number of errors. These results led us to postulate the existence of two processes (operator building and general planning) , independent of each other, but involved equally in building the representation which guides problem solving.