Introduction: Representations play an essential role in mathematical thinking. They favor the understanding of mathematical concepts and stimulate the development of flexible and versatile thinking in problem solving. Here our focus is on their use in optimization problems, a type of problem considered important in mathematics teaching and…

Policy problems like "What should we do about global warming?" are ill-defined in large part because we do not agree on a system to represent them the way we agree Algebra problems should be represented by equations. As a first step toward building a policy deliberation tutor, we investigated: (a) whether causal diagrams help students learn to…

While different approaches to evaluation will yield different results, depending on the purpose of the evaluation this article describes an evaluation approach that was aimed at investigation of the mental models of users of the programme. The study was driven by questions about the differences in mental models of the instructional designers and…

Introduces the Knowledge Digraph Contribution (KDC) data-analysis methodology for quantitatively measuring the degree to which a given knowledge digraph can account for the occurrence of specific sequences of propositions in recall, summarization, talk-aloud and question-answering protocol data. Notes the applicability of this approach to the…