Black box software testing: A course by Cem Kaner & James Bach

Quality-Related Costs

Quality/Cost analysis is a classic tool in quality engineering. We break costs into prevention, appraisal and failure costs, and ask how we can minimize the total expenditure on quality (including what it costs to make it good, and what it costs because it wasn't good enough). This lecture shows how to apply the analysis to software products.

One of the problems with this analysis is that it computes costs only from the vendor's perspective. It's what the vendor/manufacturer has to spend to deal with a customer complaint about a defect, not the (perhaps much larger) loss caused by the defect to the customer. The point of quality-related litigation is to push back some of the customer's losses (caused by a defect) onto the company that made and sold the product with this defect. Because companies don't compute predicted customer losses in their quality/cost type models, they can be blind-sided when hit with lawsuits for recovery of the massive losses a product has caused.

We are setting up a mailing list for announcements about this course and, perhaps, a tightly focused and moderated discussion of how to teach it or self-study with it. (This won't be a general, high-traffic, intro-to-testing discussion.) If you're interested in the course, please sign up by sending us an email. We will NOT share your email address with third parties or send commercial advertising to you.

We are publishing this course under a Creative Commons license that allows you to freely reuse and distribute the materials and to modify the slides and associated printable materials (but not the videos). We would be appreciate a few mirror sites, to reduce the growing burden on our servers. If you can help in this way, or any other way, please send a note to Cem Kaner.