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The economics of unit testing

Ellims, Michael; Bridges, James and Ince, Darrel C. (2006). The economics of unit testing. Empirical Software Engineering, 11(1) pp. 5–31.

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Conventional wisdom and anecdote suggests that testing takes between 30 to 50% of a project's effort. However testing is not a monolithic activity as it consists of a number of different phases such as unit testing, integration testing and finally system and acceptance test.

Unit testing has received a lot of criticism in terms of the amount of time that it is perceived to take and its perceived costs. However it still remains an important verification activity being an effective means to test individual software components for boundary value behavior and ensure that all code has been exercised adequately. We examine the available data from three safety-related, industrial software projects that have made use of unit testing. Using this information we argue that the perceived costs of unit testing may be exaggerated and that the likely benefits in terms of defect detection are quite high in relation to those costs.

We also discuss the different issues that have been found applying the technique at different phases of the development and using different methods to generate those tests. We also compare results we have obtained with empirical results from the literature and highlight some possible weakness of research in this area.

Item Type: Journal Item
ISSN: 1573-7616
Keywords: adequacy criteria; software testing; test effectiveness; unit testing
Academic Unit/School: Faculty of Science, Technology, Engineering and Mathematics (STEM) > Computing and Communications
Faculty of Science, Technology, Engineering and Mathematics (STEM)
Interdisciplinary Research Centre: Centre for Research in Computing (CRC)
Item ID: 3620
Depositing User: Michelle Bailey
Date Deposited: 30 Jun 2006
Last Modified: 04 Oct 2016 09:50
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