Actually, this is a fermi problem. [1] The purpose of this question is to figure out if someone can break a question down into parts and estimate reasonable values. But even more so, it is supposed to test whether you are enthusiastic about strange and puzzling problems. [2]

Whether you think these questions are stupid or not, the right answer isn't "I give up, just google it", but rather "let me make some assumptions and calculate a value based on some estimates"

Having said that, I think the number is arround 100,000 [3]

[1] http://en.wikipedia.org/wiki/Fermi_problem [2] http://www.joelonsoftware.com/articles/fog0000000073.html [3] http://www.uh.edu/engines/epi975.htm

Dilbert: Studies have shown that accurate numbers are not that much more useful than the ones you make up.

PHB: How many studies showed that?

Dilbert: 87

I probably wouldn't give this answer in an interview, im more of the "I don't know" group of people.

p.s. Dilbert strip: http://www.dilbert.com/strips/comic/2008-05-08/

The town I grew up in is about 1,000 people, and has a gas station. Most of the small towns around that one of comparable size also have a gas station. So I figured if the population is about 300,000,000 and people per gas-station is about 1,000, then there are about 300,000 gas stations in the U.S.

Maybe you'd get a better figure going by number of pumps per person and then <strike>making up</strike> coming up with an average number of pumps per station. For example, (I'm guessing that) the lone gas station in a 200 person down doesn't have a lot of pumps.

http://www.infoplease.com/askeds/number-gas-stations-us-1995...

If you want the candidate to show his reasoning abilities by making good guesses based on reasonable assumptions, you should tell him to do so beforehand.

I'm a hardware engineer. As shocking as this may be to some, much of what I need to know cannot be easily found on the internet. I have to crack open a book to find good high level information. With the rising popularity of open college classes, this will probably change, but we aren't there yet.

For programming, the internet can be a very good resource. When I was a full-time programmer, google served as a very good reference. I would open a browser before I took a look at my bookshelf.

I want practical, get the job done type people.

I don't want cowboys who are more interested in clever solutions and/or impressing others with their knowledge, "obvious" intelligence, or skillz.

I certainly don't want some douche sitting in his chair theorizing from first principals when they could have googled the answer or asked team mate for help.

Finally the era when what one knows was self-contained in their heads is over. My memory and knowledge are huge and they are kept in google and wikipedia.

It shows that someone is willing to go and seek out the answer on their own.

My first job out of college, they made me an offer at the beginning of the interview process, because I'd interned with them before and they had a fairly good idea what I could do. The rest of the interviews were basically get-to-know-the-people-hired-after-your-internship.

Also, at bigger companies, your referral may not be from the group or specialty you'll actually be working with, and so you'll have to go through the interview process itself to make sure they can stand you. My Google application process was like this, and my IBM one would've been had I pursued it. It's still a big positive, that someone in the company is willing to vouch for you.

Your 1987 Impala has finally bit the dust. You call a tow truck to haul it away to be crushed or recycled. Before turning the keys over to the driver you ask “What are your biggest flaws?”

*You and your family are taking a trip by plane. You are all a little nervous, as most people are when flying. To assuage your fears to walk up to the pilot and ask him “How many crosswalks are in New York City?”"

Certainly puts things in perspective. This seems an excellent criterion for determining what are good and bad interview questions, assuming that your goal is actually to hire someone to do a job.

Exactly! Maybe pilots should interview pilots about the nuances of piloting (and once that talk is over, probably ask him to fly with the interviewer in teh copilot role) and leave out the "where do you see yourself in five years" type questions?

It's a conversation starter. It gives them a baseline to open things up. Your answers after that, once you've gotten into the swing of things, determine whether you'll be hired.

Also, an interviewer will almost never ask you "Can you do this job?" or "What does this job entail?" How do they know you're being truthful, or even if you are, how do they know that you're not just wrong? It's your responsibility to show the answer to these, through the questions you ask your interviewers. Nearly all interviewers will ask "Do you have any questions for me?" - that's your chance to show that you're interested in the meat of the job itself.

My experience with Google HR in general was very positive, though of course "all's well that ends well", so my perspective might be a bit biased.

After that they referred me to YouTube (is that where they send the second class programmers?) I had one phone interview and he asked me to come up with an algorithm to do something tricky (forget exact question) but it turns out I can't program in my head over the phone. I emailed him the solution later but I guess it didn't help.

Insightful! I guess I happen to be the very rare counterexample in that at some point in every interview process I've been through, I've been asked questions like the ones the author says won't get me hired.

And I've never been asked "can you do this job?" (not so bluntly anyways, though obviously you are evaluated on that to some degree)

Those questions don't mean you are not getting hired at all. They are (for better or for worse) standard practice by HR personnel. They might not tell you anything about a candidates capacity to do a job, but a lot of times personality fit is just as important. And I can tell a lot about a person by their answers to really stupid questions (even if they are canned, planned out, rehearsed responses).

I want to work with cool people and have the pleasure of doing so. If competency was the only factor my firm asked for when hiring, I'd probably be working somewhere else.

Ability is a necessary, but insufficient condition for employment, in my opinion.

THATS why the employers ask you the questions that "Mean You're Not Getting Hired"

Basically, they want to know how useful you are for this job and if this project tanks are we going to need to fire you or can you be used to do some other task.

I've done my share of hiring in the last couple of years, allow me to opine on this post.

"Tell me about yourself." Common question, usually my first question with candidates just to let them talk a bit about themselves and let them tell me what they feel is important. It also just breaks the ice even with a (hopefully) easy question. It doesn't mean you're not getting hired.

"What are your biggest flaws?" - I don't use this, its a bullshit question and I don't know anyone who does. No one in their right mind is going to tell you the truth. "What are you strengths" is however a decent question, like "tell me about yourself" it allows the interviewee to tell you something about themselves that you may have missed.

"Where do you see yourself in 5 years?" - Not actually a dumb question, most people don't use it correctly. The answer to this question can be useful from a "goodness of fit" perspective. Do their goals align with how your organization works? This isn't a make or break question but it can get interesting answers.

"Tell me about a time when you..." - Sorry this is the main type of question you should b e asking. This is the opportunity to ask the question "how are you going to solve the problems that we're going to give you?"

"How many gas stations are in the United States?" - Ya crap question, but some engineering managers like them.

Probably what you really want is someone who solves problems not someone who can eloquently describe problems and their solutions, under pressure, in a few minutes or less.

That question is a classic example of testing the wrong thing.

It's better for you to describe an actual problem and have them solve it or discuss how they would go out solving. Which btw is typically a needed skill (being able to reason out and weigh solutions with a team)

An example that I've used before, "What would you do if you're convinced a more senior developer is choosing the wrong solution? (usually I'll present something obviously inferior to another choice, point isn't technical but how someone would try to resolve a conflict)"

Thankfully, any smart interviewer already knows this. Being asked these questions is a sign you might not want to work for these people because they are not very smart and/or don't think about the things that they say.

To be honest, in the interviews where I thought "wow, these people know what they're doing", they did not ask these questions.

What does it matter if a certain question shows up in an interview? Why try to analyze every word? In the end, you either did well, or you didn't, and they either did well, or made a bad impression on you. Just answer the question and remain friendly whether you still think you're interested in them or not--not all questions are going to be highly technical. At the end of the day, it's just another person sitting across the table.

Finally, I don't think the "how many gas stations are there" type of questions are totally pointless (though I don't generally ask them.) They reveal something about how a candidate attempts to solve problems, and the one thing you don't want to see is the candidate simply say "I have no idea..." without at least trying. I think there is a danger if a company over relies on such questions, however.

My only flaw is that I don't have any flaws.

A super-hacker-who-can-do-the-job might be useful to hire for a specific project, but will they be a useful employee when the company decides to change directions or technologies?

In this case, I use it to gauge how an applicant handles a somewhat inappropriate question that he/she probably shouldn't answer honestly.

"Yes, that's why I applied for the job."

Correct answer: Over 9000.