Abstract:
Two instructional design features hypothesized to affect problem solving performance, problem format and contextual interference, were investigated. Problem format was manipulated by altering the format of worked examples to demonstrate a molar or modular solution. Contextual interference was manipulated by randomizing the order in which problem categories were studied. Participants studied worked examples from 5 complex probability categories and solved 11 novel problems. The modular problem format reduced study time and the workload during study and increased performance on the subsequent test. Greater contextual interference increased study time but had no effect on workload or test performance. Additionally, a regression analysis demonstrated that mental workload partially mediated the effect of problem format on test performance. A separate regression analysis did not demonstrate that working memory capacity moderated the effect of problem format on mental workload.