In 3 experiments, we examined the effects of using concrete and/or abstract visual problem representations during instruction on students' problem-solving practice, near transfer, problem representations, and learning perceptions. In Experiments 1 and 2, novice students learned about electrical circuit analysis with an instructional program that included worked-out and practice problems represented with abstract (Group A), concrete (Group C), or abstract and concrete diagrams (Group AC), whereby the cover stories were abstract in Group A and concrete in Groups C and AC. Experiment 3 added a 4th condition (C-A) with a concrete cover story and abstract diagrams. Group AC outperformed Groups A and C on problem-solving practice in Experiments 1 and 2 and outperformed Group C on transfer across the 3 experiments; Group AC also outperformed Group C-A in Experiment 3. Further, Group A outperformed Group C on transfer in Experiments 2 and 3 and outperformed Group C-A in Experiment 3. Transfer scores were positively associated with the quality of the diagrams and the number of abstract representations drawn during the transfer test. Data on students' learning perceptions suggest that the advantage of Group AC relies on the combined cognitive support of both representations. Our studies indicate that problem solving is fostered when learners experience concrete visual representations that connect to their prior knowledge and are enabled to use abstract visual representations.
Keywords: abstract visual representation, concrete visual representation, problem solvingHow can teachers help novice students develop problem-solving skills and positive learning perceptions? Research in wellstructured domains, such as physics and mathematics, has shown that one promising method consists of initially demonstrating the problem-solving process with worked-out examples and later engaging learners in guided problem-solving practice (Atkinson, Derry, Renkl, & Wortham, 2000;Koedinger & Aleven, 2007;Renkl, 2005;Renkl & Atkinson, 2003). In past studies with novice college students, we found that this method can successfully promote the transfer of learned principles to novel electrical engineering problems (Moreno, Reisslein, & Delgoda, 2006;Moreno, Reisslein, & Ozogul, 2009a). Despite these favorable outcomes, the assumptions underlying the design of the visual representations corresponding to the worked-out and practice problems (e.g., electrical circuit diagrams) were not tested.The design of the visual representations in our past studies was based on the typical diagrams used in college engineering textbooks, which mostly represent electrical engineering problems with abstract diagrams. An abstract diagram provides a schematic depiction of an engineering problem and uses standard engineering symbols (Alexander & Sadiku, 2004;Irwin & Nelms, 2005), such as the zig-zag symbol to represent a light bulb. In contrast, we define concrete electrical engineering diagrams as those that provide realistic illustrations of the real-life electrical e...