VIEWPOINT
The role of replications in Empirical
Software Engineering
Forrest J. Shull & Jeffrey C. Carver & Sira Vegas &
Natalia Juristo
Published online: 29 January 2008
# Springer Science + Business Media, LLC 2008
Editor: Claes Wohlin
Abstract Replications play a key role in Empirical Software Engineering by allowing the
community to build knowledge about which results or observations hold under which
conditions. Therefore, not only can a replication that produces similar results as the original
experiment be viewed as successful, but a replication that produce results different from
those of the original experiment can also be viewed as successful. In this paper we identify
two types of replications: exact replications, in which the procedures of an experiment are
followed as closely as possible; and conceptual replications, in which the same research
question is evaluated by using a different experimental procedure. The focus of this paper is
on exact replications. We further explore them to identify two sub-categories: dependent
replications, where researchers attempt to keep all the conditions of the experiment the
same or very similar and independent replications, where researchers deliberately vary one
or more major aspects of the conditions of the experiment. We then discuss the role played
by each type of replication in terms of its goals, benefits, and limitations. Finally, we
highlight the importance of producing adequate documentation for an experiment (original
or replication) to allow for replication. A properly documented replication provides the
details necessary to gain a sufficient understanding of the study being replicated without
requiring the replicator to slavishly follow the given procedures.
Empir Software Eng (2008) 13:211–218
DOI 10.1007/s10664-008-9060-1
F. J. Shull
Fraunhofer Center for Experimental Software Engineering, College Park, MD, USA
e-mail: fshull@fc-md.umd.edu
J. C. Carver (*)
Mississippi State University, Mississippi State, MS, USA
e-mail: carver@cse.msstate.edu
S. Vegas
:
N. Juristo
Universidad Politécnica de Madrid, Madrid, Spain
S. Vegas
e-mail: svegas@fi.upm.es
N. Juristo
e-mail: natalia@fi.upm.es