This study is a quasi experiment comparing the software defect rates and implementation costs of two methods of software defect reduction: code inspection and test-driven development. We divided participants, consisting of junior and senior computer science students at a large Southwestern university, into four groups using a two-by-two, between-subjects, factorial design and asked them to complete the same programming assignment using either test-driven development, code inspection, both, or neither. We compared resulting defect counts and implementation costs across groups. We found that code inspection is more effective than test-driven development at reducing defects, but that code inspection is also more expensive. We also found that test-driven development was no more effective at reducing defects than traditional programming methods.

Writing my first textbook was an eye-opening experience. I had to dig deep. I had ideas I was excited about and found others that were excited about them as well. I also found strong opposition to my approach, which was difficult for publishers to evaluate. My experience raised a number of questions that I have outlined below. These questions range from personnel motivation to future trends in computing. I have gathered a panel of respected authors. I have asked each to respond to some of these questions. Time will also be available for the audience to ask questions and share their own experiences.