In previous hiring tips, I suggested you ask behavior description interviewing questions and perform auditions. I haven't discussed hypothetical questions yet, because they can be difficult to frame well.
In response to my current Stickyminds column about how to improve tester performance. Suzan Noden said she uses this as a question: “how would you test the ls (or dir) utility?”. A surface answer involved options and output. A deeper answer might involve timestamps, permissions and directory depths. An even better answer would include different types of filesystems, network mounts, etc.”What a great hypothetical question. Anyone who knows anything about Unix has the capacity to answer this question and show off their testing skills.
A manual black box tester might say something like this, “Look to see that the output is alphabetical in columns,” a surface answer. A more knowledgeable person might say, “Let's set up a possible race condition by having two processes modify the files at the same time as another process attempts to ls. A tester who knows about different devices might discuss timing and the response time of certain disk drives or other drives.
Hypothetical questions help you understand how the other person thinks they think. Unfortunately, the way people think about themselves is not necessarily how they act, but that's why you have behavior description interviewing questions.You can effectively use hypothetical questions to learn if the candidate has deep knowledge of the subject. Then follow up with behavioral interviewing questions to see if the candidate has ever used their knowledge on the job.