You are required to read and agree to the below before accessing a full-text version of an article in the IDE article repository.

The full-text document you are about to access is subject to national and international copyright laws. In most cases (but not necessarily all) the consequence is that personal use is allowed given that the copyright owner is duly acknowledged and respected. All other use (typically) require an explicit permission (often in writing) by the copyright owner.

For the reports in this repository we specifically note that

  • the use of articles under IEEE copyright is governed by the IEEE copyright policy (available at
  • the use of articles under ACM copyright is governed by the ACM copyright policy (available at
  • technical reports and other articles issued by M‰lardalen University is free for personal use. For other use, the explicit consent of the authors is required
  • in other cases, please contact the copyright owner for detailed information

By accepting I agree to acknowledge and respect the rights of the copyright owner of the document I am about to access.

If you are in doubt, feel free to contact

Effects of Negative Testing on TDD: An Industrial Experiment

Publication Type:

Conference/Workshop Paper


International Conference on Agile Software Development, XP2013




In our recent academic experiments, an existence of positive test bias, that is lack of negative test cases, was identified when a test driven development approach was used. At the same time, when defect detecting ability of individual test cases was calculated, it was noted that the probability of a negative test case to detect a defect was substantially higher than that of a positive test case.The goal of this study is to investigate the existence of positive test bias in test driven development within an industrial context, and measure defect detecting ability of both positive and negative test cases. An industrial experiment was conducted at Infosys Ltd. India, whose employees voluntarily signed up to participate in the study and were randomly assigned to groups utilizing test driven development, test driven development with negative testing, and test last development. Source code and test cases created by each participant during the study were collected and analysed.The collected data indicate a statistically significant difference between the number of positive and negative test cases created by industrial participants, confirming the existence of positive test bias. The difference in defect detecting ability of positive and negative test cases is also statistically significant. As a result, similarly to our previous academic study, 29% of all test cases were negative, contributing by revealing as much as 71% of all the defects found by all test cases. With this industrial experiment, we confirmed the existence of a positive test bias in an industrial context, as well as significantly higher defect detecting ability of negative test cases.


author = {Adnan Causevic and Rakesh Shukla and Sasikumar Punnekkat and Daniel Sundmark},
title = {Effects of Negative Testing on TDD: An Industrial Experiment},
editor = {H.Baumeister and B. Weber},
month = {June},
year = {2013},
booktitle = {International Conference on Agile Software Development, XP2013},
publisher = {Springer},
url = {}