Work is the refuge of people who have nothing better to do. : Oscar Wilde

Wednesday, April 7, 2010

Interview Questions May Look Weird

... without being at all unreasonable.

Ten interview questions keep appearing for discussion again and again on the 'net. Here's how they appeared on wired.co.uk a couple of days ago.

"How many tennis balls are in this room and why?"
Asked at Yahoo

"You are in a room with three switches, which correspond to three bulbs in another room, and you don't know which switch corresponds to which bulb. You can only enter the room with the bulbs once. You cannot use any external equipment (power supplies, resistors, etc). How do you find out which bulb corresponds to which switch?"
Asked at Goldman Sachs

"Are your parents disappointed with your career aspirations?"
Asked at Fisher Investments

"If I put you in a sealed room with a phone that had no dial tone, how would you fix it?"
Asked at Apple

"If you were a brick in a wall, which brick would you be and why?"
Asked at Nestlé USA

"How would you move Mount Fuji?"
Asked at Microsoft

"Develop an algorithm for finding the shortest distance between two words in a document. After the phone interview is over, take a few hours to develop a working example in C++ and send it to the manager."
Asked at Google

"Given a dictionary of words, how do you calculate the anagrams for a new word?"
Asked at Amazon

"How many hair salons are there in Japan?"
Asked at Boston Consulting

"Say you are dead -- what do you think your eulogy would say about you?"
Asked at Nationwide Insurance

The ones in blue seem to make complete sense to me inasmuch as they do relate in some obvious way to the employer's business. This is not to say that Yahoo would be interested in the number of tennis balls in a room. Or that Boston Consulting would probably be interested in the number of hair salons in Japan. But they would be interested in a candidate's ability to estimate these numbers in some reasonable way.

Similarly large parts of what both Google and Amazon do relates to processing words. Naturally they want to know whether candidates can do this with some confidence. In fact, in the case of Google I have noticed that team members in ancillary, non-technical project roles are expected to understand a good deal of the underlying technology.

I have coloured some of the questions in grey. Perhaps if I had a really high IQ I would be a better judge of these questions. As it stands though it appears to me that it would be way too easy to miss the factors that are critical for answering these correctly. Assuming that you did cleverly identify the key factors needed, how would your ability to answer the question about the lightbulbs and switches benefit Goldman Sachs?

The questions coloured orange are complete duds, in my opinion, because, without normative information no-one can accurately gauge the responses to them. However, this was really not my point. I wanted to say that careful, intentional interviewers construct interview questions that attempt to measure or probe candidates' suitability for the work they will actually do. Surely that's what they want to know.

From the candidate's perspective, my experience tells me that, if an interviewer cannot be induced to ask meaningful questions that reveal job content then don't accept a job offer. The interviewer likely doesn't know what the job entails her/himself. Assuming that this individual becomes your boss how will s/he know you've done a creditable job?

2 comments:

John FitzGerald said...

And I'd bet there are no data confirming the success of any of these items in predicting work performance, even in combination with the other items in the interview. I'd be the thickest brick, by the way.

Bill Bell said...

I wish I'd said that, John.