Using visualization to aid program construction tasks

Abstract

This paper discusses how novices exposed to an execution model of recursion (similar to an expert's mental model and visualised in the EROSI tutor) performed on the task o f constructing an embedded recursive solution to a given problem specification. Empirical observations showed that affter using the EROSI tutor, novices employed a variety o f methods during program construction including the use o f their understanding o f the execution process o f recursion from their visualisation experiences. Using our findings we provide some useful suggestions to inform teaching practice. We conclude that when teaching about recursion: visualising program execution models can be a useful aid to program construction, by providing a mental framework for reasoning about the behaviour o f program code fragments both before and after coding; visualisation methods m a y not always be a sufficient condition for developing programming skills; and the teaching o f techniques for program construction may be necessary.