The last time I took up Pair Testing was while testing Vischeck with Ajay Balamurugadas. We had teamed up on Gmail chat, tested the product in a given timeframe and shared our learnings. If you visit the comments of this post, you will realize how I goofed up my learning by completely misunderstanding the product that I tested (I intentionally have these comments in place to remind me not to repeat this mistake).
I got another opportunity to learn with a tester friend Bhargavi M who teamed up with me for Pair testing. The best part was that we got together at one place instead of Gmail chat. We mutually agreed to test ‘Play’ option in Windows Media Player. While Bhargavi(in this case, the tester) took over the keyboard to test Windows Media Player > Play option, I(in this case, the reviewer) chose to analyst and review the tests in addition to brainstorming additional ideas which Bhargavi might miss(potential misses and not intentional misses). At the end of the session, we had tested all the ideas that both of us had come up with. Please find the report HERE.
Learnings from Pair Testing
1. It is a good learning to let the tester take complete control to test while the reviewer observes/takes down notes/reviews the testing process. This is a very good way for the reviewer to learn how different the thought process of the tester is. This also points to areas where the reviewer needs to improve to test better.
2. It is a good learning for the tester to learn and understand which areas/test ideas were missed, but caught by the reviewer during the note taking process. It helps the tester to observe and learn where he/she failed to identify the test ideas that reviewer captured.
3. It is a challenge to think in diverse ways and execute all the test ideas all alone. Pair Testing is advantageous in that it is two pairs of eyes which is testing the application instead of just 1 pair of eyes AT THE SAME TIME. This not only helps in finding issues, but also enhances the investigative nature of the tester and the reviewer as they would keep on building on the test ideas one by one. If the tester missed something, there is a high probability that the reviewer would have caught this and vice versa.
4. Pair testing gives more insight into the tester's scenario testing process. Each tester’s thinking and understanding about scenario testing is different and hence executed differently.
5. Pair testing yields good benefits when the tester and the reviewer’s skills complement each other. If both end up being similar personalities with same set of skills, knowledge, intuition etc, they might end up missing critical bugs which would have been caught as a result of their diverse nature.
6. Pair testing is different from Pairwise testing.
NOTE: I have called one person as the tester and the other as the reviewer because the reviewer's job is mainly to note down observations and add new test ideas. However, the reviewer can contribute to the testing at any time.
Thanks to Bhargavi M for the wonderful Pair Testing Experience.
Addendum on 6th Oct 2009
A good document on Exploratory Testing in Pairs.