Gayle Laackmann reports (link from Felix Salmon) that Microsoft, Google, etc. don't actually ask brain-teasers in their job interviews. The actually ask a lot of questions about programming. (I looked here and was relieved to see that the questions aren't very hard. I could probably get a job as an entry-level programmer if I needed to.)
Let's look at the very widely circulated "15 Google Interview Questions that will make you feel stupid" list [here's the original list, I think, from Lewis Lin] . . . these questions are fake. Fake fake fake. How can you tell that they're fake? Because one of them is "Why are manhole covers round?" This is an infamous Microsoft interview question that has since been so very, very banned at both companies . I find it very hard to believe that a Google interviewer asked such a question.
We'll get back to the manhole question in a bit.
Lacakmann reports that she never saw any IQ tests in three years of interviewing at Google and that "brain teasers" are banned. But . . . if brain teasers are banned, somebody must be using them, right? Otherwise, why bother to ban them? For example, one of her commenters writes:
I [the commenter] have been phone screened by Google and so have several colleagues. I can say that the questions are different depending on who is asking them. I went in expecting a lot of technical questions, and instead they asked me one question:
"If I were to give you $1000 to count all the manholes in San Francisco, how would you do it?"
I don't think you can count on one type of phone screen or interview from Google. Each hiring team probably has their own style of screening.
And commenter Bjorn Borud writes:
Though your effort to demystify the interview process is laudable you should know better than to present assumptions as facts. At least a couple of the questions you listed as "fake" were used in interviews when I worked for google. No, I can't remember ever using any of them (not my style), but I interviewed several candidates who had other interviewers ask some of these. Specifically I know a lot of people were given the two eggs problem. Which is not an entirely unreasonable problem to observe problem solving skills.
And commenter Tim writes:
I was asked the manhole cover question verbatim during a Google interview for a Datacenter Ops position.
What we seem to have here is a debunking of a debunking of an expose.
Who do we believe?
You'll be unsurprised to hear that I think there's an interesting statistical question underlying all this mess. The question is: Who should we believe, and what evidence are we using or should be using to make this judgment?
What do we have so far?
- Felix Salmon implicitly endorses the analysis of Laakmann (who he labels as "Technology Woman"). I like Salmon; he seems reasonable and I'm inclined to trust him (even if I still don't know who this Nouriel Roubini person is who Salmon keeps mocking for buying a 5 million dollar house).
- Salmon associated the "fake" interview questions with "Business Insider," an unprofessional-looking website of the sort that clogs the web with recycled content and crappy ads.
- Laackman's website looks professional (unlike that of Business Insider) and reports her direct experiences at Google. After reading her story, I was convinced.
- There was one thing that bugged me about Laackmann's article, though. It was the very last sentence:
Want to see real Google interview questions, Microsoft interview questions, and more? Check CareerCup.
I followed the link, and CareerCup is Laackmann's commercial website. That's fine--we all have to earn a living. But what bothered me was that the sentence above contained three links (on "Google interview questions," "Microsoft interview questions," and "CareerCup")--and they all linked to exact same site. That's the kind of thing that spammers do.
Add +1 to the Laackmann's spam score.
- I didn't think much of this at first, but then there are the commenters, who report direct experiences of their own that contradict the blog's claims. And I couldn't see why someone would bother to write in with fake stories. It's not like they have something to sell.
- Laackmann has a persuasive writing style, but not in the mellow style of Salmon (or myself) but more in the in-your-face style Seth Godin, Clay Shirky, Philip Greenspun, Jeff Jarvis, and other internet business gurus. This ends up being neutral for me: the persuasiveness persuades me, then I resist the pushiness, and the net is to be neither more or less convincing than if the article were written in a flatter style.
What do I think? I'm guessing that Laackmann is sincere but is overconfident: she's taking the part of the world she knows and is generalizing with too much certainty. On the other hand, she may be capturing much of the truth: even if these wacky interview questions are used occasionally, maybe they're not asked most of the time.
My own story
As part of my application to MIT many years ago, I was interviewed by an alumnus in the area. We talked for awhile--I don't remember what about--and then he said he had to go off and do something in the other room, and while I was waiting I could play with these four colored cubes he had, that you were supposed to line up so that the colors on the outside lined up. It was a puzzle called Instant Insanity, I think. Anyway, he left the room to do whatever, and I started playing with the cubes. After a couple minutes I realized he'd given me an impossible problem: there was no possible way to line up the cubes to get the configuration he'd described. When he returned, I told him the puzzle was impossible, and he gave some sort of reply like, Yeah, I can't figure out what happened--maybe we had two sets and lost a couple of cubes? I still have no idea if he was giving this to me as some kind of test or whether he was just giving me something to amuse myself while he got some work done. He was an MIT grad, after all.