Classification Tree

I am really happy to introduce the classification tree based testing methodology which was used by our team. We had a story which was too huge to be tested in a single stretch and also had a lot of combination data to be tested. Sampling of input data and testing was one solution. Now it was even difficult for us as it had a lot number of combinations. I can give you an example of the scenario.

I had to test all the parameters related to a catalog and product where each of them had more than 20 parameters. Each parameter had more than 4 values each to be tested. So we have a permutation and combination of a minimum of 160 test cases to be executed for testing the functionality. This was not possible within the given duration. So i decided to go ahead with the classification tree methodology.

Whats Classification tree?

The Classification Tree Method is a method for test design, as it is used in different areas of software development. It has been developed by Grimm and Grochtmann in 1993. Classification Trees in terms of the Classification Tree Method must not be confused with decision trees.

The classification tree method consists of two major steps:

1. Identification of test relevant aspects (so called classifications) and their corresponding values (called classes) as well as
2. Combination of different classes from all classifications into test cases.

The identification of test relevant aspects usually follows the (functional) specification (e.g. requirements, use cases …) of the system under test. These aspects form the input and output data space of the test object. (courtesy: wiki)

Where to get the classification tree software?

CTE XL tool is available for download at http://www.berner-mattner.com/en/berner-mattner-home/products/cte-xl/. 

The Classification tree software helps to develop the classes and identifies all the test cases available for the scenario. Now once the tree is developed for the scenario the TC's can be selected based on the coverage from the available TC developed from the tree. Thus this provide an overview on all the TC's available for the scenarios and the QA can decide on which one is to be selected for execution based on coverage analysis.