Garbage in, garbage out? An empirical look at oracle mistakes by end-user programmers

End-user programmers, because they are human, make mistakes. However, past research has not considered how visual end-user debugging devices could be designed to ameliorate the effects of mistakes. This paper empirically examines oracle mistakes - mistakes users make about which values are right and which are wrong - to reveal differences in how different types of oracle mistakes impact the quality of visual feedback about bugs. We then consider the implications of these empirical results for designers of end-user software engineering environments.