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Ask HN: Do you expect interviewees to “ace” whiteboard coding exercises?

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Re: Ask HN: Do you expect interviewees to “ace” whiteboard coding exercises?

#41

Post by d4rkph1b3r »

eranation wrote: post #16

My two cents: (not hiring for a well known west coast company, but still) This is how I rank candidates. Let's say for a common question such as lowest common ancestor in a BST. 1. if they know the solution already and tell me they know it - major points, most interview prep books include it and they came prepared and they are also honest. I let them implement it still (and add some twist of my own) 2. If they don't…

I'm a little confused. You are saying you don't want people to be familiar with implementing an algorithm before you ask it? Like are there actually candidates who can come up with implementing red black tree rotation on the fly without ever having seen it, be it class or a book?

Can you clarify?

Re: Ask HN: Do you expect interviewees to “ace” whiteboard coding exercises?

#42

Post by eranation »

d4rkph1b3r wrote: post #41
eranation wrote: post #16

My two cents: (not hiring for a well known west coast company, but still) This is how I rank candidates. Let's say for a common question such as lowest common ancestor in a BST. 1. if they know the solution already and tell me they know it - major points, most interview prep books include it and they came prepared and they are also honest. I let them implement it still (and add some twist of my own) 2. If they don't…

I'm a little confused. You are saying you don't want people to be familiar with implementing an algorithm before you ask it? Like are there actually candidates who can come up with implementing red black tree rotation on the fly without ever having seen it, be it class or a book? Can you clarify?

Well, depends on the question.

If it's a hard question, there are two options, if they know it already, great, I still would like to see it implemented. If not then I would like to see how they ask me questions and respond to hints and I'll help them get to the solution. I don't expect them to do years of algorithmic research on the fly, no. Example will be

If it's an easier question, I do expect them to come up with a solution on their own even if they never heard of it. Example will be a 2 sum question. Or rotations a matrix (just examples, I'm not saying that this is what I ask)

Hope I clarified.

Re: Ask HN: Do you expect interviewees to “ace” whiteboard coding exercises?

#43

Post by RogerL »

sown wrote: post #26
eranation wrote: post #16

My two cents: (not hiring for a well known west coast company, but still) This is how I rank candidates. Let's say for a common question such as lowest common ancestor in a BST. 1. if they know the solution already and tell me they know it - major points, most interview prep books include it and they came prepared and they are also honest. I let them implement it still (and add some twist of my own) 2. If they don't…

> f you can't figure it out yourself but ask me questions, if you try a simpler problem first, if you talk and explain what you are doing, if you run your ideas with me asking what I think, if you are determined to figure it out, ask for hints and immediately understand them and get this "aha" moment of how didn't I think of it rather than oh sucks I didn't think of it. I don't understand what you mean with this sent…

Some interviewers think they have innate abilities that even the best trained psychologists don't have. They are deluded. If you fail that interview you dodged a bullet (assuming you aren't 30 days from foreclosure or something).

Re: Ask HN: Do you expect interviewees to “ace” whiteboard coding exercises?

#44

Post by liquidcool »

crdb wrote: post #27

I used to (and, a few years ago, turned away smart people who failed them), but realized they were the wrong test for a small company. I switched initially to getting people to complete a task in their own time with the resources they liked and send us the code, and now entirely on network (i.e. who our CTO has already worked with and knows). Big companies can't afford that luxury though. If big companies set tasks,…

I agree with the work sample test. In similar threads, some found cheaters, but the followup interview exposed them because they can't speak about the process and solution cogently. I imagine that if you look at enough, just reading them will allow you to spot cheaters, and having so many applicants will provide a good selection ethical developers. And a short contract-to-hire or probation period should deal with any who get through.

Re: Ask HN: Do you expect interviewees to “ace” whiteboard coding exercises?

#45

Post by crdb »

liquidcool wrote: post #44
crdb wrote: post #27

I used to (and, a few years ago, turned away smart people who failed them), but realized they were the wrong test for a small company. I switched initially to getting people to complete a task in their own time with the resources they liked and send us the code, and now entirely on network (i.e. who our CTO has already worked with and knows). Big companies can't afford that luxury though. If big companies set tasks,…

I agree with the work sample test. In similar threads, some found cheaters, but the followup interview exposed them because they can't speak about the process and solution cogently. I imagine that if you look at enough, just reading them will allow you to spot cheaters, and having so many applicants will provide a good selection ethical developers. And a short contract-to-hire or probation period should deal with any…

The other issue with judging sample code is the sheer amount of time it takes. The two of us took around 3 months (full time, effectively, doing nothing else) to select, interview and make offers to around 10 employees out of a pool of over 100 qualified applicants.

You can sort of understand why companies try to develop less time consuming methods, and why experienced developers prefer to hire from their network...

Re: Ask HN: Do you expect interviewees to “ace” whiteboard coding exercises?

#46

Post by liquidcool »

crdb wrote: post #45
liquidcool wrote: post #44

Earlier quoted context omitted.

I agree with the work sample test. In similar threads, some found cheaters, but the followup interview exposed them because they can't speak about the process and solution cogently. I imagine that if you look at enough, just reading them will allow you to spot cheaters, and having so many applicants will provide a good selection ethical developers. And a short contract-to-hire or probation period should deal with any…

The other issue with judging sample code is the sheer amount of time it takes. The two of us took around 3 months (full time, effectively, doing nothing else) to select, interview and make offers to around 10 employees out of a pool of over 100 qualified applicants. You can sort of understand why companies try to develop less time consuming methods, and why experienced developers prefer to hire from their network...

Thanks for the data on the evaluation time. 9-10 hours per applicant is nontrivial, I agree. If you've worked with someone shoulder to shoulder, I can also see that being as effective. The problem I hear is that depending on the experience and number of the founding team, they can exhaust their network quickly.

Peopleware has the idea of auditions, and I thought if you were clear about what you wanted, applicants would be comparable. I'm thinking, "Walk us through a project you did that demonstrates your knowledge of code quality." Or similar, with a clear list of what you're hoping to see.

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