A bug's eye view of immediate visual feedback in direct-manipulation programming systems
Papers presented at the seventh workshop on Empirical studies of programmers - ESP '97
Immediate visual feedback is becoming a common feature in direct-manipulation programming systems of all kinds-from demonstrational macro builders to spreadsheet packages to visual programming languages featuring direct manipulation. But does immediate visual feedback actually help in the domain of programming? We previously reported on an empirical study to determine whether the inclusion of immediate visual feedback into a direct-manipulation programming system helps with one particular task:
... debugging. In that study, subjects debugged programs with and without immediate visual feedback. We found that although immediate visual feedback did not significantly help with debugging in general, it did significantly help with debugging in some circumstances. In this paper, we follow up on those results, looking at attributes of the bugs themselves to see if they help to determine the circumstances in which feedback helps with debugging. We analyze how particular bugs and collections of bugs grouped by error type related to subjects' debugging abilities with and without immediate visual feedback, which we term the "which" questions; how bugs' position on the screen related to subjects' debugging abilities with and without immediate visual feedback, termed the "where" questions; and whether the presence or absence of immediate visual feedback affected the speed and order in which bugs were corrected, termed the "when" questions. The results show that a bug's error type and screen position were together a strong predictor of whether feedback would aid in identifying and correcting it, and that these two factors also significantly influenced how feedback affected the speed and order in which the bugs were corrected.