Dark Motives and Elective Use of Brainteaser Interview Questions • Hacker News Board

Re: Dark Motives and Elective Use of Brainteaser Interview Questions

#191

Post by 8_hours_ago » Tue, Sep 11, 2018, 9:23 PM UTC

vivekseth wrote: post #171

8_hours_ago wrote: post #123

I recently interviewed at Apple and one interviewer caused me to decide to never work there. I was put into a conference room and had 8 people over 6 hours come in and interview me one after another. Each person asked me about my background and then jumped into a whiteboard coding problem. Most of the interviewers were understanding of the fact that writing code on a whiteboard is nothing like writing code on a compu…

So you will never work at Apple because you had 1 bad interviewer out of a sample size of 8? That seems foolish.

As a programmer I have the ability to be selective with the jobs that I take. The first 7 interviewers did not convince me that Apple was a good place to work. The last interviewer convinced me that I didn't want to work with them or people like them.

Of course, things change. It would be difficult for Apple to change my mind about working there, but it is not impossible. Ask me again in 10 years :)

Re: Dark Motives and Elective Use of Brainteaser Interview Questions

#192

Post by mgkimsal » Tue, Sep 11, 2018, 9:34 PM UTC

jkingsbery wrote: post #149

expertentipp wrote: post #71

Earlier quoted context omitted.

Satisfacton from saying this during an interview at Google would be worth not getting the job:)

TRUE STORY: I interviewed at Google earlier in my career. In one of the interviews, the interviewer asked me to recite/reconstruct off the top of my head the convex hull algorithm. I remembered the lectures in undergrad algo class where the professor talked about it. I remembered where in CLRS it was covered. I remembered the general outline (efficient algorithms are O(n log n), because you have to sort the points as…

> "What if you were a Google engineer, and you had to solve this problem, what would you do?"

Well... I might ask one of the other people on the team (or in the company) for some help. Because I'm probably going to ask one of them for a review (or someone else will review it anyway). No man is an island, etc.

What did Sergey and Larry do to solve these problems? They hired more people!

Re: Dark Motives and Elective Use of Brainteaser Interview Questions

#193

Post by ultraluminous » Tue, Sep 11, 2018, 9:34 PM UTC

hectormalot wrote: post #178

nicoburns wrote: post #131

Earlier quoted context omitted.

What I find weird about these questions, is that they are expected to be answered without any research? How often do you expect your people to solve a problem in a domain they know nothing about without doing any research? And the given example is odd, a lot of useful information that would help to answer the question will be public, and the obvious way to answer the question would be to look it up, before estimating…

In the context that I've seen them used, the interviewer usually provides information if asked (and says so up front). e.g. if you don't know the # of inhabitants of Italy it should be completely okay to ask. In any case I don't think it is about the calculation or the final number. It's really the approach that you develop that's interesting. I've seen this mostly used in (management)consulting though, where you act…

The problem is that the interviewer asks for a number. If the question was phrased as "How would you go about finding out the GoogleAds B2B revenue in Italy for 2017, which tools and methods would you use", I'd totally go for that question.

The reason is that to many people (myself included) your answer above is nonsensical.

  “With ~50M people capable of clicking ads, and assuming they click one ad a day at 20cnt CPC, it would be around 3.6bn. I think my assumptions are on the high side, but order of magnitude is probably correct”

Where did the "people capable of clicking ads" 50M estimate come from? Why one ad a day on average? Why not 0.2? Or 15? Why 20c CPC and not 0.001 euro cent? Why not 1USD?

I'm all for "first-principals based structured thinking" but asking someone to demonstrate that by generating a rudimentary formula, that won't survive any contact with reality, and populate it with almost completely random values, seems like a weird way to go about it.

Re: Dark Motives and Elective Use of Brainteaser Interview Questions

#194

Post by mgkimsal » Tue, Sep 11, 2018, 9:35 PM UTC

gcatalfamo wrote: post #16

grivescorbett wrote: post #14

Earlier quoted context omitted.

This isn’t a brain teaser. It’s market size estimation, I’m guessing this was not an engineering role?

How is that question different from "please estimate how many golf ball fit in a school bus" ? The only thing changing are parameters. EDIT: it was for the Search team, search spam prevention, can't remember role it's been 4-5 years, sorry.

If someone is sending emails about golf balls and school busses, it's probably spam. ;)

Re: Dark Motives and Elective Use of Brainteaser Interview Questions

#195

Post by mgkimsal » Tue, Sep 11, 2018, 9:39 PM UTC

corey_moncure wrote: post #128

8_hours_ago wrote: post #123

I recently interviewed at Apple and one interviewer caused me to decide to never work there. I was put into a conference room and had 8 people over 6 hours come in and interview me one after another. Each person asked me about my background and then jumped into a whiteboard coding problem. Most of the interviewers were understanding of the fact that writing code on a whiteboard is nothing like writing code on a compu…

So you met 8 people, and one of them was a jerk? I'd say that's a pretty acceptable jerk coefficient for a workplace. I've been in places north of 0.5.

That they allowed that person to be a representative of the company when someone is interviewing the company to decide if they'd want to work there... that's a bad PR move. Yes, the company extends an offer on their end, but really, both parties are making decisions. If they can't put their best foot forward.... that's a problem. If they think this was their best foot forward, that's another problem.

Re: Dark Motives and Elective Use of Brainteaser Interview Questions

#196

Post by mgkimsal » Tue, Sep 11, 2018, 9:44 PM UTC

pmiller2 wrote: post #183

01100011 wrote: post #143

Earlier quoted context omitted.

I'm nitpicking, but yes sometimes you do have to code under pressure. Yes it can result in bad code but it can also save millions of dollars as production lines are allowed to run, ecommerce is allowed to happen, or important contractual obligations are met. That said, you generally do not write that code on a whiteboard with no access to the internet. It sounds like you just interviewed with a dick. That happens.

I don't believe your nitpick is valid here. True, sometimes one has to code under pressure, in the sense that money is lost (or, at least not made) while things are down, but there's almost never a situation where you can't stop and take an extra 20 or 30 minutes to check to see that your code would do what you expect it to do. In fact, if the worst consequence of waiting 30 minutes to deploy a temporary fix is that…

> but there's almost never a situation where you can't stop and take an extra 20 or 30 minutes to check to see that your code would do what you expect it to do

The implication in these examples is that you're doing it on your own, always, and... that's generally bad, especially with a known bug. Most of the bugs I have created have been ones where I've specifically not talked through the logic with someone else (usually a client/stakeholder, or domain expert, or whatever) to determine that my understanding is correct (might need more tests or to adjust existing tests to reflect a better understanding of the issue, etc). These 'emergency bug fixes that must be dealt with on the spot in minutes!' scenarios are more likely that cause of the issues in the first place.

Re: Dark Motives and Elective Use of Brainteaser Interview Questions

#197

Post by sangnoir » Tue, Sep 11, 2018, 9:50 PM UTC

segmondy wrote: post #68

throwawaymath wrote: post #59

Earlier quoted context omitted.

Would you say the questions that fund asked you are relevant to the work you do (or would be doing) there? I think that's the core criticism most people levy against the "high tech" interview questions.

People that don't get the offer tend to complain about such things. They are asking questions to measure how you think, to measure your potential, to see how you handle stress. If you are stressing over an interview, what will you do when you lose $1 million in 10 seconds?

> They are asking questions [...] to see how you handle stress.

I've got a time-saving suggestion - instead of asking questions, measure how long interviewee holds up while being waterboarded. If they can handle that stress, they can handle losing $100 million in 10 seconds, easy.

Re: Dark Motives and Elective Use of Brainteaser Interview Questions

#198

Post by titanix2 » Tue, Sep 11, 2018, 10:01 PM UTC

jkingsbery wrote: post #149

expertentipp wrote: post #71

Earlier quoted context omitted.

Satisfacton from saying this during an interview at Google would be worth not getting the job:)

TRUE STORY: I interviewed at Google earlier in my career. In one of the interviews, the interviewer asked me to recite/reconstruct off the top of my head the convex hull algorithm. I remembered the lectures in undergrad algo class where the professor talked about it. I remembered where in CLRS it was covered. I remembered the general outline (efficient algorithms are O(n log n), because you have to sort the points as…

> "What if you were a Google engineer, and you had to solve this problem, what would you do?"

"I would Google it", and this time the answer is very corporate! Still not what's expected by the interview, but it would be funny to watch him argue that the main product of its employer is not qualified for the task.

Besides, I find it silly too to ask for details that are easily found in printed material, with less probability of mistake than remembering it.

Re: Dark Motives and Elective Use of Brainteaser Interview Questions

#199

Post by justfor1comment » Tue, Sep 11, 2018, 10:13 PM UTC

To account for some interviewers being sadist in general, may be companies can implement a per interviewer rejection quota. For example, if you interview 10 candidates at max you can reject 7 candidates. You have to yes to 3 candidates or be removed from the interviewing committee. This will ensure that just one bitter person is not preventing good candidates from clearing the interview process.

Re: Dark Motives and Elective Use of Brainteaser Interview Questions

#200

Post by munchbunny » Tue, Sep 11, 2018, 10:16 PM UTC

jfasi wrote: post #181

munchbunny wrote: post #175

Earlier quoted context omitted.

At risk of proposing a generalization, I think that this comes from the same place that other gatekeeping behaviors come from: you see yourself as the in-group's bouncer. That puts you in a mindset to run the interviewee through a gauntlet, partly as a ritual to show their desire to get in, and partly through a sense of duty to hire "only the best". But hiring is not a filtering problem. It's a matching problem. And…

I've been mentally drafting a blog post on exactly this topic, so while that percolates in my mind I'll answer with: it totally is a filtering problem. For a small company whose culture is in flux and needs the right person, it's absolutely a matching problem. You need to find the right person for the job, period. At the scale of a company like Google, however, it's absolutely a filtering problem. First off, we're la…

> Second off, the number of applications rejected for every hire is staggering, simply because of how many people apply. These numbers are fantasy, but imagine if you had to choose one person out of a hundred applicants, and you actually had the means to interview every single one. You're going to pay this person a quarter of a million dollars a year and aim to keep them for half a decade or more. The economically rational thing to do is be picky as all hell, and this is exactly how Google and friends do it.

That's a good point. It's hard to ignore just how many applicants you filter out in the hiring process. However, Google and Facebook are exceptions in terms of having a non-differentiated hiring test. They are very big exceptions, but still exceptions. They have a standard interview bar and matching with teams comes later. On the other hand, Microsoft, Apple, Amazon, Samsung, Adobe, etc. all hire for specific roles.

I think the way to reconcile the nuance I was getting at with "matching problem" is this: "picky as all hell" must still be fair and backed up by a clear idea of why your requirements are as tough as they are. When you see yourself as a gatekeeper you're more likely to lose sight of that.