In Search of What We Experimentally Know about Unit Testing

Gathering evidence in any discipline is a lengthy procedure, requiring experimentation and empirical confirmation to transform information from mere opinion to undisputed fact. Software engineering is a relatively young field and experimental SE is even younger, so undisputed facts are few and far between. Nevertheless, ESE´s relevance is growing because experimental results can help practitioners make better decisions. We have aggregated results from unit-testing experiments with the aim of identifying information with some experimental basis that might help practitioners make decisions. Most of the experiments focus on two important characteristics of testing techniques: effectiveness and efficiency. Some other experiments study the quality of test-case sets according to different criteria