Multi-method research: An empirical investigation of object-oriented technology

There is a general acceptance that software engineering research should be supported by empirical evaluation. To make real progress researchers must a ddress the difficulties caused by the human-intensive nature of software de velopment as well as experimental validity. This payer proposes the use of multi-method empirical research programs, as an alternative to 'single-shot ' empirical studies, to help address these problems. The multi-method approach is based on the combination of complementary empi rical research methods. The intention is that the complementary nature of t he research methods compensate for weaknesses inherent in individual method s. It is argued that the multi-method approach potentially provides benefit s in terms of more robust conclusions, development and investigation of res earch hypotheses in an evolutionary manner, and increased understanding of research results. This paper demonstrates an application of the multi-method approach in an e mpirical investigation of object-oriented technology. This research program consists of a set of structured interviews with practitioners of object-or iented technology, followed by a wide-scale questionnaire survey, and concl udes with a set of three controlled laboratory experiments which investigat ed one of the key findings from the exploratory interview and questionnaire phases. This application finds evidence that unconstrained inheritance usa ge in object-oriented software may inhibit software maintenance. The paper concludes that the multi-method approach offers the possibility o f more reliable and generalizable results from empirical software engineeri ng research. (C) 1999 Elsevier Science Inc. All rights reserved.