Thursday, March 08, 2012
I practically shouted "Amen!" when I read, in a blog posting, an admonition against asking "nano questions" when interviewing potential employees. From the title -- "I'm an engineer, not a compiler." -- I had a fairly good guess as to what a "nano question" might be, but here's an example, taken from the field of computer science:
It seems like technical interviews have become more and more focused on the tiny trivial pursuit details of technology: "So, Mr. Olsen, exactly which version of Java were you using in this project, was that 188.8.131.52.3.1 or 184.108.40.206.3.2?" Who remembers? Who cares? The kind of knowledge that is wrapped up in knowing the difference between V1.2a and V1.2c has approximately the same shelf life as unrefrigerated shell fish. I'm certainly not telling you to not to ask technical questions. By all means do ask technical questions. But there is a difference between a technical question What is inheritance? What is the downside of using Java? and questions that could appear in Trivial Pursuit/Geek Edition.The so-called "nano question" -- whose answer one could easily look up (if he ever needed it) -- merely indicates factual knowledge on some very specific topic; the broader questions require relevant knowledge to answer and, more importantly, a conceptual understanding of that knowledge.
Computers are great a coughing up trivia, but only humans can conceptualize, and that is presumably why they're being hired. It follows that the cost of screening humans as if they were computers (or computer programs) is that good candidates can and will get passed over. The post excerpted above goes on:
Aside from telling you not much at all, the tiny question has two real costs: first it takes up the time that you could be spending getting to know this person, finding out if they are smart enough, if they have the right background, if they will fit into your group. The second cost of this kind of question is that it tends to tick off those smart, well rounded people that you really do want to hire.The first post I linked indicates a possible trend, noting that many certification exams ask such questions, and provides a pithy rule of thumb: "Any question that takes 5 seconds to answer with Google is not a good question."
But it's only a rule of thumb: Some things that look like nano questions aren't, and may be the kind of knowledge one must have readily accessible in memory to get the job done. (I am sure that lots of information used by emergency medical personnel might fall into this category.) I learned this not-always-obvious distinction the hard way about twenty years ago: When I was a junior officer in the submarine force, I confused a question about the basis for a normal operating limit with a nano question -- during a qualification board interview! I basically replied that I could just look up the answer if I needed it. "Wrong answer!" is what the Captain said. Why? In some kinds of emergencies, it could well be necessary to know the "trivia" cold. I was rightly thrown out and had to take that board again.