PPIG 1995 - 7th Annual Workshop
MADLab: Masking and Multiple Bug Diagnosis
Allan scott
Abstract: Multiple bug modelling involves the construction of procedural student models in which there are more than one bug. Multiple bug modelling is interesting because it poses difficulties for hand diagnosis and may provide a means of explaining the bug instability found in empirical data. Previous work on multiple bug modelling has identified muitiple bug interactions as a challenge for diagnostic algorithms (Burton, 1982). The term bug masking is used here to define the situation where there is no simple relationship between the presence of an atomic bug in a multiple bug hypothesis and the performance of the hypothesis. The Masking and Diagnosis Lab (MADLab) is a domain independent toolkit designed to investigate the role of bug masking in multiple bug diagnosis. Experiments with the MADLab system in the domains of Prolog unification and Prolog control have provided evidence on the causes of bug masking and the effect of bug masking on the difficulty of multiple bug diagnosis.