6 ms·

If the candidate says they don't know a topic, that is a valid response. It's not worthwhile to ask detailed questions about the topic. That's a sign of an inex

by manfre 4y ago

If the candidate says they don't know a topic, that is a valid response. It's not worthwhile to ask detailed questions about the topic. That's a sign of an inexperienced and/or unprepared interviewer.

pclmulqdq 4y ago
Asking someone "how many prime numbers are there?" seems pretty valid to me. It's an easy question. The two valid answers are: "a lot" or "infinite" (with "more than 10" also being a fine answer IMO). I'm not sure the interviewer was expecting the actually correct answer here (infinite) - lots of programmers don't know that there are infinite prime numbers - I think he was trying to set up for an explanation of an algorithms problem. By saying "Optimus Prime," OP has shown that he prefers to cover up gaps in his technical knowledge with snark and being an asshole rather than taking a stab at it and working in good faith. That answer would have disqualified him in my opinion. Even respectfully saying "I thought I was intervieweing for a Django tooling position" would have opened the door to further conversation.
- Verdex 4y ago
  If the job had been some sort of super low level position requiring a lot of hand written advanced data structures, then I might agree with you. Hashes, priority queues, skip lists, etc all rub up against more math heavy topics (number theory, statistics), so you would expect a candidate to at least have some familiarity with prime numbers. However, for a web framework? Like, primes are pretty simple, but they're also pretty niche. What range of 'easy' questions that are not directly or indirectly related to the job are allowed to be asked? Can we ask questions about the correct leavening agents to use for different types of bread? I mean technically we're just trying to see how they cover up gaps in their technical knowledge. And all questions are 'easy' for the right people. If you lure someone into a place with the promise of gainful employment and then waste their time with niche questions that are unrelated but you happen to have warm fuzzies about, then you should probably expect to get a bit of snark.
  - pclmulqdq 4y ago
    I think if you're going to ask a subsequent question about an algorithm for predicting when bread is done proving, you are allowed to ask about leavening agents. That way, you can bypass the long explanation, and just say "Given n loaves of bread with X characteristics, design an algorithm to predict when they are done proving." That might actually be a decent data science interview question. I used to ask an algorithms interview question based on bridge (the card game), and I asked a setup question of "have you ever played a trick-taking game?" That lets me see if I need to use the short explanation or the long explanation, and if you answered that you knew how to play bridge or spades in a follow-up question, I would ask a much harder version. If you've never played a card game in your life, I would switch questions (this has happened several times). In real life, most people understand that this kind of question is a setup for a subsequent algorithms problem, not a quiz of your knowledge of bridge or prime numbers (particularly after you say that you don't know number theory). The interviewer didn't care how much you know about prime numbers any more than I cared about whether you knew how to play hearts/bridge. The interviewer was almost certainly trying to figure out how much he needed to explain in the problem statement for the algorithms problem. Responding with snark only shows that you are not willing to work with them in good faith, and you are not willing to see where the question is going. It shows that you think you know what they should be asking you, and you have contempt for them because they are not running the interview the way you prefer. By the way, if the primes thing was actually a quiz question that didn't go anywhere, I would encourage any Django programmer to say a gentle "fuck you" at the end of the interview. I certainly would.
  - checkmypythons 4y ago
    Still, whether or not the question was valid/appropriate/useful doesn't really matter. On the job, sometimes you will be asked things you don't know, or things you shouldn't even be responsible for knowing. The way this person responded to receiving a question like that indicates that they might be a difficult person to work with. The interviewer sounds probably bad. After the person made it clear they didn't know about number theory, they should have moved to a different topic. But still, answering "Optimus prime" just suggests immaturity or even combativeness in the face of a difficult situation, which isn't someone you want to hire. There are a thousand better answers. Even snarky answers are fine as long as the person is meaningfully engaging. "I don't know. Probably a lot" "Maybe infinite. I'm not sure." "It's an interesting question. Am I allowed to look it up?" (As someone else said) "Definitely more than 10. Outside of that I'm not sure." "I don't know. But here is how I would write a script to figure it out" It comes back to the "move mt. fuji" style questions mentioned in the article. The point of an interview is not to determine whether you would be able to move mt. fuji anymore than whether you are able to answer the number of primes. It's about how you communicate and approach a problem. "Optimus prime" is such a non-starter that it doesn't even allow for a discussion. I'm speaking as someone who passed a google interview and worked there for several years, so there may be some reason to believe my feelings around interview approaches are based in fact.
- leetrout 4y ago
  This was a ways in to the interview and I do not think I was being as asshole. I didn't say it in a mean way or anything. I was laughing about it and said I had no clue and wasn't something I was interested in. He came in ready to grill me and I did not then, nor do I now, see any benefit to adversarial interviews. I said I knew nothing when he asked about number theory. I never tried to cover up anything in my gaps. The interviewer proceeded to ask questions about it. I don't have a CS degree, I have never claimed I did or that I enjoy or even want algorithms heavy jobs. This was an internal tool to manage datacenter component ordering. I would never ask a bunch of questions about something borderline esoteric to someone that has already said they don't know anything about the field. I have had plenty of interviews where I am doing the hiring and when I realize the candidates are in over their heads I politely ask some fielding questions (like, do you know number theory is great, and fair) and then just conclude the interview kindly or toss them a different set of questions depending on how the interview has been going.
  - pclmulqdq 4y ago
    I assume you were flustered by that point due to a previous interview, and feeling a little frustrated or defeated. I've been there, when I think it's not going well but they still want to talk. Nevertheless, it appears to me that those were setup questions for his real problem to figure out how to explain it. If you had approached it with a more open mind, you may have gotten the job. You would have at least heard the question. I know that most people here hate the Google-style algorithm problem, but I think the question he was going to ask would be about computing the nth prime or counting the primes less than k. I will also point out that many people who know nothing about number theory know that there are infinite prime numbers. It's not necessarily redundant.

by manfre 4y ago

pclmulqdq 4y ago

Asking someone "how many prime numbers are there?" seems pretty valid to me. It's an easy question. The two valid answers are: "a lot" or "infinite" (with "more than 10" also being a fine answer IMO). I'm not sure the interviewer was expecting the actually correct answer here (infinite) - lots of programmers don't know that there are infinite prime numbers - I think he was trying to set up for an explanation of an algorithms problem. By saying "Optimus Prime," OP has shown that he prefers to cover up gaps in his technical knowledge with snark and being an asshole rather than taking a stab at it and working in good faith. That answer would have disqualified him in my opinion. Even respectfully saying "I thought I was intervieweing for a Django tooling position" would have opened the door to further conversation.

Verdex 4y ago
If the job had been some sort of super low level position requiring a lot of hand written advanced data structures, then I might agree with you. Hashes, priority queues, skip lists, etc all rub up against more math heavy topics (number theory, statistics), so you would expect a candidate to at least have some familiarity with prime numbers. However, for a web framework? Like, primes are pretty simple, but they're also pretty niche. What range of 'easy' questions that are not directly or indirectly related to the job are allowed to be asked? Can we ask questions about the correct leavening agents to use for different types of bread? I mean technically we're just trying to see how they cover up gaps in their technical knowledge. And all questions are 'easy' for the right people. If you lure someone into a place with the promise of gainful employment and then waste their time with niche questions that are unrelated but you happen to have warm fuzzies about, then you should probably expect to get a bit of snark.
- pclmulqdq 4y ago
  I think if you're going to ask a subsequent question about an algorithm for predicting when bread is done proving, you are allowed to ask about leavening agents. That way, you can bypass the long explanation, and just say "Given n loaves of bread with X characteristics, design an algorithm to predict when they are done proving." That might actually be a decent data science interview question. I used to ask an algorithms interview question based on bridge (the card game), and I asked a setup question of "have you ever played a trick-taking game?" That lets me see if I need to use the short explanation or the long explanation, and if you answered that you knew how to play bridge or spades in a follow-up question, I would ask a much harder version. If you've never played a card game in your life, I would switch questions (this has happened several times). In real life, most people understand that this kind of question is a setup for a subsequent algorithms problem, not a quiz of your knowledge of bridge or prime numbers (particularly after you say that you don't know number theory). The interviewer didn't care how much you know about prime numbers any more than I cared about whether you knew how to play hearts/bridge. The interviewer was almost certainly trying to figure out how much he needed to explain in the problem statement for the algorithms problem. Responding with snark only shows that you are not willing to work with them in good faith, and you are not willing to see where the question is going. It shows that you think you know what they should be asking you, and you have contempt for them because they are not running the interview the way you prefer. By the way, if the primes thing was actually a quiz question that didn't go anywhere, I would encourage any Django programmer to say a gentle "fuck you" at the end of the interview. I certainly would.
- checkmypythons 4y ago
  Still, whether or not the question was valid/appropriate/useful doesn't really matter. On the job, sometimes you will be asked things you don't know, or things you shouldn't even be responsible for knowing. The way this person responded to receiving a question like that indicates that they might be a difficult person to work with. The interviewer sounds probably bad. After the person made it clear they didn't know about number theory, they should have moved to a different topic. But still, answering "Optimus prime" just suggests immaturity or even combativeness in the face of a difficult situation, which isn't someone you want to hire. There are a thousand better answers. Even snarky answers are fine as long as the person is meaningfully engaging. "I don't know. Probably a lot" "Maybe infinite. I'm not sure." "It's an interesting question. Am I allowed to look it up?" (As someone else said) "Definitely more than 10. Outside of that I'm not sure." "I don't know. But here is how I would write a script to figure it out" It comes back to the "move mt. fuji" style questions mentioned in the article. The point of an interview is not to determine whether you would be able to move mt. fuji anymore than whether you are able to answer the number of primes. It's about how you communicate and approach a problem. "Optimus prime" is such a non-starter that it doesn't even allow for a discussion. I'm speaking as someone who passed a google interview and worked there for several years, so there may be some reason to believe my feelings around interview approaches are based in fact.
leetrout 4y ago
This was a ways in to the interview and I do not think I was being as asshole. I didn't say it in a mean way or anything. I was laughing about it and said I had no clue and wasn't something I was interested in. He came in ready to grill me and I did not then, nor do I now, see any benefit to adversarial interviews. I said I knew nothing when he asked about number theory. I never tried to cover up anything in my gaps. The interviewer proceeded to ask questions about it. I don't have a CS degree, I have never claimed I did or that I enjoy or even want algorithms heavy jobs. This was an internal tool to manage datacenter component ordering. I would never ask a bunch of questions about something borderline esoteric to someone that has already said they don't know anything about the field. I have had plenty of interviews where I am doing the hiring and when I realize the candidates are in over their heads I politely ask some fielding questions (like, do you know number theory is great, and fair) and then just conclude the interview kindly or toss them a different set of questions depending on how the interview has been going.
- pclmulqdq 4y ago
  I assume you were flustered by that point due to a previous interview, and feeling a little frustrated or defeated. I've been there, when I think it's not going well but they still want to talk. Nevertheless, it appears to me that those were setup questions for his real problem to figure out how to explain it. If you had approached it with a more open mind, you may have gotten the job. You would have at least heard the question. I know that most people here hate the Google-style algorithm problem, but I think the question he was going to ask would be about computing the nth prime or counting the primes less than k. I will also point out that many people who know nothing about number theory know that there are infinite prime numbers. It's not necessarily redundant.