Tutorial C

Test Design with Data Combination Testing and Classification Trees

Rik Marselis

09:00-17:00 CEST Tuesday 7th June

Test case design is one of the core competences of the quality engineering & testing profession. If you want to properly shape your testing, which test design technique(s) do you use? And is this effective and efficient?

Suppose you must test the entry-check of the new Wuthering Heights Rollercoaster in the QualityLand amusement park. Every person must be at least 120 cm tall to be allowed in the rollercoaster. What technique would you use? Boundary Value Analysis, right? That’s not a tough choice. But now the product owner of QualityLand has made the situation much more complex. The height of people is split in 3 categories: less than 120 cm is not allowed, from 120 to 140 cm people will get a seat-extender and people taller than 140 cm are allowed. If the total weight of the people on the ride is between 700 and 1000 kg the ride will go. If the total weight is less than 700 kg extra weight-blocks are added. And if the total weight exceeds 1000 kg people must stay behind to get the right weight.

So, now you have 2 data items, with together 6 possible values. What test case design technique do you use? And what coverage can you achieve?

In the above example choose a data-oriented test design technique. But which?

In this situation, the Data Combination Test design technique, which uses Classification Trees, is a very suitable technique. And because this technique can be combined with 3 different coverage types you have a great way to align with the risk level of the application. So, in your test strategy, you can vary the test intensity from low (with all values of data items used at least once) to medium (with pairwise coverage of the data items) and to high intensity (with all combinations of all values used).

Join me in this full-day tutorial about DCT & CT and I will make sure that you can use the techniques (with our Excel and Powerpoint templates) at the very next day you return to work.