Replication's Role in Software Engineering

We provide motivation for researchers to replicate experiments in software engineering. The ideology of replication is discussed. We address the question: Is an experiment worth repeating? The current lack of replication studies is highlighted. We make clear that exact replication is unattainable and we draw on our first experience of performing an external replication. To categorise various kinds of replication, we propose a simple extension to Basili et al.’s framework for experimentation in software engineering. We present guidance as to the level of reported detail required to enable others perform a replication. Our conclusion is that there is only one route for empirical software engineering to follow: to make available laboratory packages of experimental materials to facilitate internal and external replications, especially the latter, which have greater confirming power.