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Google admits brainteasers were useless for hiring (2013)
- ma2rten 8y ago[2013]
- ggggtez 8y agoI was gonna say, I haven't heard anyone talk about brain teaser interviews in years. Now everyone just complains that whiteboarding is not a good measurement instead.
- jeffreyrogers 8y agoHere are two thoughts on tech interviews. One controversial and one (hopefully) not. 1. It's good that companies like Google are able to reassess their hiring policies and learn what works and what doesn't. It's easy to criticize companies for doing things that don't make sense or that we know to be bad, but often these things looked like good ideas at the outset and you need some amount of trying new things (many of which won't work out and may have negative consequences) in order to improve things. 2. The way hiring works in tech isn't really that bad. It doesn't really measure what matters for job performance but tech pays well and so many people want to do it that you need barriers to entry. The real losers of the hiring process are the companies that waste lots of money on inefficient hiring practices. If you compare the effort required to get a high paying tech job (really just doing practice problems for a few weeks/months) to any other high paying, professional field we have it much better.
- ksk 8y ago> The real losers of the hiring process are the companies that waste lots of money on inefficient hiring practices. In this case though, how is 'lots of money' wasted? It seems that Google hired good candidates despite some of the questions being bad. I think the point here is that Google is looking to increase the efficiency in interviewing, but they're already at a high efficiency level anyway so they continue to be successful in attracting and keeping talent.
- bluGill 8y agoWell sure, there are a lot of good candidates. Most bad candidates don't even apply. What if instead of reading resumes/interviews/whatever else they did they just put all the names into a hat and made offers to everyone selected? This is your baseline, does your process beat this? If not, you could save a lot of time/effort using the hat selection method. (note that it is possible to be worse than the hat method)
- ddorian43 8y agoWTF type of interviews do lawyers, doctors, engineers have ?
- deleted 8y ago[deleted]
- jeffreyrogers 8y agoIt's not the interviews. It's what it takes to even get an interview. Doctors have 4 years of med school, then 3-7 years of residency, then probably a fellowship if you're in a competitive specialty. Lawyers get 3 years of law school and then probably only get a job at a good firm if they went to a top law school. Then they work terrible hours. Finance jobs are very hard to get unless you have the right background. Other engineers might have an easier interviewing process but they don't get paid as well (plus they need a real engineering degree).
- deaddodo 8y agoPetroleum Engineers (US median - 129,990USD) and Computer Engineers (111,730 USD) are some of the highest paid engineers there are. And quite a few are in the same realm as Software Engineers (100,690 USD): * Electrical Engineer - 95,230 USD * Chemical Engineer - 97,360 USD * Mechanical Engineer - 83,590 USD * Biomedical Engineer - 86,220 USD And when you consider the skewing of those salaries due to the majority of software engineers working in LA (and surrounding SoCal areas), SF, Austin, Denver and New York vs petroleum engineers working throughout the interior US, the gap is much larger. Software engineers are paid well, but there are definitely other engineering fields beating them.
- sanderjd 8y agoI mostly agree with both of your points, but I also think "we have it much better" depends on which "we" you're talking about. Our practices are better for people trying to break in and worse for seasoned professionals. It's more time consuming (and less well-paid) to become a nurse, but once you have done so, you don't have to do it again every time you switch jobs.
- kingbirdy 8y agoI am very happy to take a month of brushing up on algorithms and so on every few years as I want a new job as opposed to an additional several years of school.
- draw_down 8y agoHow is that a response to GP’s point?
- e40 8y agoIn the example given, a nurse wouldn't need additional schooling to switch jobs.
- szermer 8y agoEveryone in the medical profession needs continuing education (CE) credits. Not much different from certs that support folks need to obtain if they work government/ DoD positions. https://www.nurse.com/state-nurse-ce-requirements https://www.nurse.com/state-nurse-ce-requirements
- vonmoltke 8y agoCE classes for nearly all professions are a joke compared to the shit software engineers are expected to go through to rehearse for interviews. As for government work, I'm not sure where you got that idea from. I did government work for 14 years and never needed any certifications. If I had, the company would have paid for it and it would have been on company time.
- majormajor 8y ago> If you compare the effort required to get a high paying tech job (really just doing practice problems for a few weeks/months) to any other high paying, professional field we have it much better. So here's the selfish-as-a-hiring-manager side of not liking the current style of interview questions: I don't want my bar to be so low that studying for a few weeks or months is all it takes. One or two medium-level problems to make sure they're not full of shit about being able to write code at all, sure, but the rest is gonna be a lot more targeted to the role.
- bluGill 8y agoIf you are a great programmer, then within two weeks of working with me you will be great at my company - in fact when asked how you are doing I will be shocked when I realize that you have only been here 2 weeks instead of 5 years.
- majormajor 8y agoSo what are you saying here? You only hire great programmers? And they all shock you in the same way? Or you hire some mediocre ones too who don't shock you that way? And how do you interview them?
- TooBrokeToBeg 8y ago> So what are you saying here? You only hire great programmers? I'm not sure how you could have confused what was posted, to be interpreted that way.
- majormajor 8y agoI asked because the relevance was not evident to me, in a discussion of hiring processes, unless it was directly related to his own hiring process in some way.
- GavinMcG 8y agoGiven that he did it might be more helpful to offer a better interpretation, rather than just being dismissive.
- xamuel 8y agoI come from academia and can confirm your #2. If you want to get a professor job, it's all about letters of recommendation, publication in prestigious journals, talks at prestigious conferences, etc. Programming interviews are extremely fair and meritocratic by comparison.
- robotresearcher 8y agoYou imply that strong reference letters, strong publications and talks at top conferences are obtained unfairly. Why do you think so? If you look at the batch of assistant professors that start every year at good schools, did they pick the wrong people?
- foldr 8y ago>You imply that strong reference letters, strong publications and talks at top conferences are obtained unfairly. Why do you think so? There's no implication that the letters are obtained unfairly, but that doesn't necessarily mean that the resulting outcomes are fair. The point is that if you find yourself in a situation where you can't get hold of these things and yet you are, in fact, really good, there's nothing much you can do about it short of waiting a few more years and hoping to build up a better professional reputation. In contrast, you can just show up at a coding interview, demonstrate that you can in fact code (at whatever level is required), and land a job. Case in point: I moved from academia to coding by doing this (without any relevant qualifications or having worked professionally as a software engineer). There is no equivalent progression for someone who wants to move to academia from coding.
- robotresearcher 8y agoThe equivalent to acing a code interview for an academic is submitting a terrific paper. Papers are typically submitted to open calls without any referrals. If the paper has an impact, the rest of it follows. Prestigious invited talks don't come out of the blue, but usually as a result of consistent work that people care about. If a researcher can't get their papers published, in an activity where that is a key metric of success and the key communication medium, what's the basis of the 'really good' assessment? Look at the list of keynote speakers at any major conference you understand. Are those the wrong speakers? Did they get this privilege unfairly?
- k1ns 8y agoI recently interviewed at a well-known software company, was turned down, and have very mixed feelings about the entire situation. I was tasked with a total of 7 coding problems, 5 of which took place in an onsite interview that lasted around 5 hours. The problems were fun, the interviewers were great, and I'd ultimately rate the experience as the best hiring process I've been a part of. I personally think that these problems were exactly the type that tech companies need to be using as they were focused on creativity and your thought process as opposed to some "genius detector" brain teaser. I passed each problem with flying colors, except for the final one. The point of this final exercise was for me to talk through my thought process. It was a debugging problem, and I eventually succeeded, but not without fumbling around for 15 minutes or so. The solution was a stereotypical example of being "right in front of you", but the nature of this exercise threw me off. When I look back, the analogy that makes the most sense to me is the boxing glove wall from the TV show, Wipeout [1]. It's a simple problem of getting from point A to point B with the twist of getting punched in the face, or the stomach, or the leg, at seemingly arbitrary intervals. I can see this as a good simulation for the reality of an engineering job (being faced with unplanned interruptions and having to bounce back from them) but, at the same time, I've never had to verbally talk someone through every keystroke and mouse movement that I make while debugging. I was frustrated with the exercise and with my inability to immediately diagnose the issue. The interviewer was amazing at getting me back into the right mindset after noticing I had fallen off the wagon each time, which showed me just how good of a manager they were. However, the more I realized how terrible I was doing, the worse I performed. I left with the unmistakable feeling of dread having set-up camp in my stomach. Despite arriving at the solution, I knew I had blown that exercise. In the end, I was turned down. The official reason was that another candidate had accepted an offer for the position, but the hiring manager also told me that my programming skills were perceived as sub-par due to the final exercise. They said I'd be a great fit culturally, and that their team enjoyed the conversations we had, but my Python skills just weren't good enough. Being someone that really identifies with their abilities as a programmer, with Python being my language of choice, this verdict has kept me awake at night. I'll never know if the actual reason was due to the other candidate accepting or due to me being my own worst enemy during the final exercise. The tech hiring process is one of the only times I've gotten 100% of the problems correct yet still failed. Half of me says that's bad, but another part of me understands in situations that require context like mine above. It's not the manager's job to babysit me when I psych myself out, or when I'm having a bad day. Engineers need to be reliable and stable enough to work efficiently on their own. Had I been alone, I would have found the solution much quicker. But you're almost never alone in a real work environment. Some of these exercises are measuring much more than just algorithmic competency. [1] https://www.youtube.com/watch?v=0XGmcQPCSG4 https://www.youtube.com/watch?v=0XGmcQPCSG4
- watwut 8y ago"It doesn't really measure what matters for job performance but tech pays well and so many people want to do it that you need barriers to entry. The real losers of the hiring process are the companies that waste lots of money on inefficient hiring practices." The other losers are people who have skills and aptitude that is actually needed, but don't have the thing that interview measures. Yet other losers are people forced who have to work with those who ace interviews and get rewarded, but are not actually good in actual work. The side note is not just that hiring don't really measure what matters for job performance. It is also that companies themselves don't really seriously care about it nor spend time thinking about it. That affects not just hiring, but also promotions and other rewards. Which in turn causes additional problems and unhealthy workplaces (excessive crunch being one of those, huge amount of socialization that is expected in some companies another, ridiculous technological decisions too and so on and so forth).
- taurath 8y agoThe focus on hiring is not about assessing job performance. This is absolutely clear to me after spending a bit of time as a contract worker with an exemplary record and a page full of recommendations from full time employees of many levels, who still has to pass through the same hiring gatekeeping process. Its now HR required that everyone be interviewed in the same manner. Performance means nothing in the interview - and the interview absolutely has nothing to do with the job, its just a bunch of alg questions. Its incredibly frustrating and disheartening to know how much they are skewing towards people who can pass the test rather than people that can excel at the job.
- watwut 8y agoI think that "everyone is interviewed in the same manner" thing can eventually evolve into better hiring process - because it will overtime produce data that can be learned from. But, I also think that it will end up split into different kinds of interviews for different positions. The older I am the more I believe that there is no single "good in tech" aptitude and that such notion is nonsense. Rather, different tech jobs require very different amounts of abstract thinking, logic, patience, memory, aesthetic feel, detailed knowledge of some sub-area, ability to communicate, self control, punctuality and so on and so forth. You can be quite crappy at assembler and heavily talented for enterprise java for example. You can be good at smaller projects and completely fundamentally fail in large codebase many people situation.
- guyzero 8y agoThis is a five-year old article about something Google stopped doing in about 2010. But on the off chance you're 8 years behind the times, it turns out that those infamous brainteasers were completely useless for hiring at Google.
- theDoug 8y agoSurfacing old news for Hacker News to build karma points is too-frequently a successful play. All you have to do is slap a (2010) and all gets forgiven.
- meritt 8y agoI don't think it's karma per-se, I think it's his marketing strategy. Take this very specific instance and we have: 1) OP submits 2-3 stories per day 2) OP comments far less frequently than his submission rate and those comments are almost never on his own submissions 3) OP's profile contains contact information for him as a B2B consultant and a link to his blog
- slededit 8y agoIt's not like the information has gone bad in the meantime.
- gxs 8y agoYou know, there are a lot of cool things I've learned that I wouldn't have learned if reposts were strictly controlled. I would even hypothesis that an ideal web community in the vein of reddit or HN is not completely void of reposts. There must be some ideal percentage that makes the site most useful/successful. Don't know where on the number line those figures land, but sharing something that crosses my mind when I see a repost. HN seems to have a decently low number, IMO.
- kens 8y agoI'm somewhat baffled by the article. I started at Google in 2004 and it wasn't using brainteasers like "A man pushed his car to a hotel and lost his fortune" or "Why are manhole covers round" even then. It was mostly challenging algorithm and programming problems. I think there's a lot of urban legend in these brainteaser questions.
- logfromblammo 8y agoThe businessinsider.com article linked by posted qz.com article has some hilariously bad answers for the leaked Google interview questions. Most of them distill down to "here's how we would make a clever attempt to avoid answering that question, by answering an easier one" and some are followed by "here's a smarter answer, submitted by a reader infuriated by our published response".
- Blackstone4 8y ago> Google now relies ... “behavioral interviewing,” such as asking people to describe a time they solved a difficult problem. Is it just me? I feel like I've always had good reviews but I struggle to answer questions like these in interviews.
- burkaman 8y agoIt is hard, but it's very common and pretty easy to prepare for. I don't think it's unreasonable to expect candidates to have stuff like this ready to go.
- majormajor 8y agoHopefully there's a different bar for different roles. If you're someone who's been a technical manager for 5 years, and I'm asking you about, say, a time you had to give (or receive, for that matter) negative feedback, then if you've never had to do that I might question the breadth of your experience and readiness a bit. I think the key here is to be very specific about the type of situation you're looking for, and to ask a bunch of them to get a broad look at the person's experience.
- maxxxxx 8y ago" describe a time they solved a difficult problem." I actually like this type of question either as being interviewer or the interviewee. At least it allows me to demonstrate the thought process I put into a problem I actually encountered instead of talking about stuff I never had the need to do like a lot of algorithmic stuff.
- CobrastanJorji 8y agoI like them as an interviewee, but as an interviewer I find that they can be very challenging to grade in a consistent way. The upside to "invert a binary tree" type questions is that it's a lot easier to put together a rubric (although the downsides are myriad).
- maxxxxx 8y ago
- s-shellfish 8y agoGoogle changes the way people interact with the internet -> Google changes the way people think about how other people think -> Google uses it's own metrics of intelligence to determine intelligence WHILE Google is actively changing what intelligence is (or at least what people think it is) Hm...Sounds like a paradox right?
- lgleason 8y agoand their hiring standards have also slipped......
- bitL 8y agoThey were IMO the only funny/interesting part of their whole interview process. Now it's like a sterile academic discussion.
- mfrw 8y agoAt last, they do agree that brainteasers are not a measure of how well you can code. In my _opinion_ code & communication skills should be enough, immaterial of whether you can figure out how to measure 4 gallons using a 5 & 3 gallon jug.
- Bahamut 8y agoMaybe in a decade they'll admit their current interview process is also busted :) .
- nomel 8y agoAny insight into the current process?
- dekhn 8y agoLaszlo Block was never a useful source of information on how Google worked. He just used his position to gain attention and publish books.
- CobrastanJorji 8y agoSurely the SVP who was in charge of hiring at Google is a useful source for information on how Google hired people?
- dekhn 8y agoYou'd think, but no, not really. He mostly just wanted to sell a book.
- duckkg5 8y agoOne they asked me in 2010 was "How many people are in the air right now?" I've conducted loads of interviews at Google since 2012 and none have included a question like this from myself or any other hiring committee members.
- duckkg5 8y agoOne they asked me in 2010 was "How many people are in the air right now?" I've conducted loads of interviews at Google since 2012 and none have included a question like this from myself or any other hiring committee members. IMO the questions about what they do for fun are way better at determining if they'll fit and do well.
- loftyal 8y agoWith interviews, you are essentially trying to predict the job performance of a candidate when they are at your company, so why not make it as close to that as possible? With face-to-face tell them to bring their laptop or you can provide one, then explain a real actual hard problem you've solved or one of your colleagues has, that took roughly 2 hours, leave the room and let them try and solve it on their own accord without any pressure of people staring at them whilst coding. Come back and ask them to explain their solution and quiz them on different parts. This has been by far the best test I've given that predicted real on job performance.
- jl2718 8y agoThis seems really obvious. Why do you think nobody else does this?
- loftyal 8y agoWhiteboarding, Programming and Comp Sci Trivia is pretty rampant...
- ggggtez 8y agoTo be a true scientist, you shouldn't necessarily do what seems obvious. For all I know, maybe whiteboarding is a better indicator of performance than 1 hour of coding on a laptop. How well does it compare? I bet that's a closely guarded secret.
- AnimalMuppet 8y agoI bet that it's unmeasured, and maybe unmeasurable.
- jaypaulynice 8y agoGoogle and lots of companies continued to use brain teasers even when they realized it made no sense. Sure they wish to say this after using it for a long time. What I’ve realized sometimes there are barriers to prevent certain people and give a sense of meritocracy while justifying discrimination. It’s like when looking for an apartment, some landlords will only check some people’s backgrounds and not others. The same is true for credit card companies offering some people much lower apr than others for no reason other than prejudice. We could go on and on with examples, but that’s just a few. In the end every company becomes average because there is only so many people they can hire. This has nothing to do with brain teasers per se. I’ve worked in tech for over 10 years and I have to say the places I did the best work are interviews I somewhat bombed. Not a surprise!
- jl2718 8y agoIf google really wanted a fair and objective hiring process, it would be easy. They don’t. The coding interview is one of the most subjective processes I’ve seen in hiring. The interviewer reviews the resume, and then gives a vague problem that has many answers, only one of which they are looking for. Then they either let you flounder or straight up tell you what they want. At the end, code is erased, and interviewer gives subjective feedback. If they wanted a good process, it would be double-blind, consistent, and adjusted for efficacy. The stats that they do share show the opposite: Google’s top performers were massively over-represented among those that had the lowest interview scores. Steve Yegge himself interviewed 6 times before getting an offer. one question you might ask is whether Google even wants top performers. I don’t think so, honestly, and they say as much with their focus on culture. They want people that will go along to get along and not cause conflict by disagreement or doing things their own way. This type of cohesion is much more important to google than individual performance. The idea is that the interviewer is the expert and you are the Padawan trying to learn by exploration. Be humble and take hints. If you disagree with an interviewer, you’re done. If you do something they don’t understand, don’t try to explain, just undo it. The interviewers are randomly chosen among volunteers, and the ones that volunteer the most were shown to have the worst performance in assessment. So the lesson here is that it’s a social game. You don’t need to learn every algorithm, just know the basics of any programming language, and I’d say even prefer things like for loops to functional maps because most likely, they won’t follow. The social game, however, is an unlimited liability. You need to make the interviewer feel like the expert in their problem, and feel like they taught you something profound. This is not your performance; you are just the magician’s assistant, acting out their will.
- dukoid 8y ago"Google’s top performers were massively over-represented among those that had the lowest interview scores" -- source?
- gwbas1c 8y agoThe biggest problem with hiring, IMO, is finding an effective filter. My employer now works with contracting firms where about 80% of the candidates they send us are excellent and we hire. The interview is almost a formality. When we reject a candidate, it's usually because the candidate is a bad fit for the job. (Edit) The rejects are always very talented and would succeed in different assignments. When we hire for employees through a recruiter, the process is much harder. Most of the candidates recruiters bring us are, to put it mildly, horrible and incompetent. (Edit) The recruiter doesn't really filter for competency. The medical profession has an industry-wide certification process. I wish we had the same, because it would be easier to filter out the morons.
- rogerbinns 8y agoWhat is the difference between a "recruiter" and a "contracting firm"? It sounds like both are sending you candidates you hope to hire.
- gwbas1c 8y agoLook up what out-sourcing is. Most of the time, when a company needs to develop software, it doesn't make sense to hire all developers as on-site, full-time, permanent positions. Some people are only hired for the project and go away when the project is done. Those people are hired through a contracting firm; and the contracting firm finds them employment when the project is complete. For us, it's easier to "hire" through the contracting firm because they usually worked with each other in past projects. A recruiter has very little direct experience with a candidate. Ironically, things would be easier if recruiters always sent us "formality" interviews and the contractors needed tighter screening. This is because it's easier to hire a contractor for 3 months and choose to renew the contract.
- chris_va 8y agoGoogle interviewers were never supposed to ask brainteaser like questions, even before the company "admitted" they don't work. The title is disingenuous, and implies that Google switched tactics after finding out that these questions were not useful, whereas in reality Google never started doing it because they found that these questions were not useful. (Source: I did interviews at Google pre-2013)
- marcodave 8y agoso where are these "interview brain teaser questions from Google" coming from?
- chris_va 8y agoI don't think these questions are uncommon in the industry. I've seen brain teaser questions from Microsoft, for example. I think when people write about them they just attach the examples to something emblematic for marketing, and then it becomes common lore.
- g9yuayon 8y agoPeople tend to forget the historical context of a policy. Google was small in the early 2000s, but it was one of the hottest companies in the valley. Therefore, it could afford being picky. It was solving really tough computer science problems in massive scale, so it needed to find talented true geeks, those who live and breath math, engineering and computer science. The so-called brainteasers were usually thinly disguised and well-designed math or algorithm questions. There were few interview-prep books back then, either. Therefore, those who could solve the teasers were likely creative geeks. Fast forward to it today, we have huge amount of prep materials and prep schools, so it becomes hard to tell who's truly talent and who has great memory. Google doubled its workforce in the past three years from 35,000 people or so to 70,000 people. You just can't expect that everyone is passionate and talented about math or engineering. Besides, Google does not need too many of this kind of people either. However, if a small company is tackling a hard problem that does require tons of math, computer science, or pure ingenuity. Hell ya, brainteasers can be of great help. They don't even need brainteasers, they can just directly ask math problems.
- opo 8y ago>...However, if a small company is tackling a hard problem that does require tons of math, computer science, or pure ingenuity. Hell ya, brainteasers can be of great help. They don't even need brainteasers, they can just directly ask math problems. Yes, if the job requires tons of math, it makes sense to ask math questions, it doesn't necessarily mean that people who are good at brain teasers will be good at the job. According to the article, what google found in regards to asking brain teasers: >...“We found that brainteasers are a complete waste of time,” Laszlo Bock, senior vice president of people operations at Google, told the New York Times. “They don’t predict anything. They serve primarily to make the interviewer feel smart.”
- mixmastamyk 8y agoRiddles fell out of favor, but now we're faced with the next disastrous trend which I just wasted an hour on yesterday---coderpad.io. Imagine a binary pass/fail test that determines your future, next to a suitcase full of cash, clock ticking, and another developer watching over your shoulder, also feeling smarter because they already know the answer. An answer they researched in solitude at a leisurely pace. Conclusion: "We can't find any qualified people, there must be a shortage."
- 0xfeba 8y agoI much prefer coderpad or HackerRank, live with the interviewers, over whiteboarding. I find talking through a first approach, improvements, debugging, etc. is very useful -- both as an interviewer and candidate. The timed HackerRank and such sucks though. Way too stressful. And easily subverted. They enforce fullscreen but you can just use another computer to look things up. I wonder if, comparatively, other fields have as many "fakes" as I've seen try to get jobs in mine. I'd say 1/20 candidates I've interviewed aren't imbeciles.
- mixmastamyk 8y agoBetter than coding on a whiteboard is hardly a complement. Maybe I didn't write clearly enough, but the reason you are attracting so many "fakes" is that you are testing for "nerves of steel" rather than coding ability and misattributing a lack of the former with the latter.
- 0xfeba 8y agoWe don't ask anything hard. For JS candidates, given [1, 2, 3, 'a'] return an array without the letter. Debug an AJAX call (the URI protocol has an obvious typo). For react candidates, implement an event handler for a button that increments and shows a value (all prewritten, just add this.setState({value: ++value}); We also guide them and give hints and encourage interaction, or if they need to think we leave them alone. If that requires too strong of nerves, uh, oh well I guess. I don't know how else to judge their technical ability and soft skills.
- davidf18 8y agoFrom the article: "Google has admitted that the headscratching questions it once used to quiz job applicants (How many piano tuners are there in the entire world?, ..." The article continues: '“We found that brainteasers are a complete waste of time,” Laszlo Bock, senior vice president of people operations at Google, told the New York Times. “They don’t predict anything. They serve primarily to make the interviewer feel smart.”' This question is called a Fermi problem, in fact the prototypical problem is, "How many piano tuners are there in Chicago?" Mr. Bock has not engineering or science background and it is unclear how he would know about hiring engineers and scientists. While the article may have misquoted Mr. Bock, but it seems as if Mr. Bock is not aware of Fermi problems and they are are certainly not "a brainteaser and a complete waste of time." The ability to come up with approximations before solving problems is truly useful in engineering and the sciences (my undergrad is BS EE/CS from top ranked school) and I have work experience in hardware and software. I would say for life in general it helps to be able to estimate quantities and being able to do Fermi problems may undoubtedly correlate with one's abilities to problem solve. Another important issue to consider is that Fermi problems are useful but that outcomes by ethnic group may have interfered with diversity hiring goals and therefore the questions were dropped. In summary, I believe that people in charge of hiring scientists and engineers have the education and work experience to understand science and engineering. Would you want nuclear power plant designers and Boeing airliner designer hired by people with a BA degree?
- contextfree 8y agoIIRC they took this practice from Microsoft, which had already abandoned it by then
- mikestew 8y agoYup, I left MSFT in 2005, and sometime before that they packed all the hiring managers in a room and told us: "brainteasers: quit doing them, they are not an indicator of anything useful." The practice didn't stop immediately, but it certainly fell out of favor shortly after amongst my crowd.
- itronitron 8y agoI got asked the water jug brainteaser in an MSFT interview, as luck would have it I had recently watched Die Hard With a Vengeance so I knew the answer :)
- akshat_h 8y agoAren't a lot of so called 'algorithmic problems' similar to brain teasers? If you have seen it before, you'll know it. But otherwise, there is not much chance of you cracking it without an 'Aha' moment, which may or may not come during the one hour allocated for an interview. Weird tricks in bit manipulation, linked lists, array, hash problems etc. are all standard in interviewing and are still used, even at Google, at least 2 years ago, when I last interviewed there. This works though as Google's, and the industry in general has a policy of rejecting candidates, rather than accepting them, because hiring is very risk-averse. Candidates switch jobs frequently at the beginning of their career and so there is a rotating pool of good candidates the companies can pick from.
- xtracto 8y agoYes they are, and as you, I consider themselves exactly the same. An example one that I used to ask during interviews were the "traverse a matrix in inverse diagonals" or "traverse a matrix in circular way" or the typical "first duplicated number" (that one is on CodeFights and CodeWars). Those are problems that you either know the "trick" or you don't. The main problem with the majority of them is not the problem itself. The main problem is that originally they are meant to understand the process of problem solving of a candidate. However, as they are passed among interviewers, they become an "solved or not solved", because it is the path of least effort. I once created a problem that I love to ask in my interviews, it deals with binary search to get the total elements from a list that is only avilable through a "broken" API. A lot of people I interviewed told me that they loved the question, however, when some colleagues started adopting it, I realized that they were basically expecting the specific answer they knew... when the real value of the exercise is to work with interviewees to "solve a problem together".
- akshat_h 8y agoI think this is also because no one really teaches you how to interview. Giving multiple interviews doesn't, at least IMHO make you knowledgeable to be on the other side. It is kinda at a certain level in your career you are expected to just know how to do it. For other skills like management, you at least have your peers who are doing the work day in day out, who you can learn from. Interviews are closed room, usually, though I have had some where one person was shadowing the interviewer. Also, if you take a terrible interview, its not gonna really impact you. There is no performance report that'll negatively impact you. There will be another candidate, who you'll have a rapport with. Or someone else will interview someone else. As you said in your anecdote about the binary search problem, not everyone is best at being an interviewer. But aside from there being a dedicated person for interviewing for big companies, or outsourcing interviews for startups, I don't really see a solution. And outsourcing, whether internally or externally comes up with its own set of problems.
- perl4ever 8y agoI'm unclear whether "brainteasers" are synonymous with "Fermi problems", or whether they are a disjoint set, or a superset. From some of the descriptions in this thread, it seems like some "brainteasers" are clearly not Fermi problems. I would be interested in knowing if anyone is hiring based on ability to do Fermi problems. I see these as not being about knowing a "trick" but about knowing how to utilize your own knowledge, which is a much more general capability.
- ncmncm 8y agoIt is really amazing, when you get into it, how many people with excellent-looking CV and experience just can't code their way out of a wet paper bag. They don't know what cache is or how to tell when you've run out of it; can't use pointers, can't write a loop; don't understand object lifetime or that objects have one; or think a null pointer is, or should be, the same as an empty string. (This last is most amazing because it seems to be official policy at Google!) The elementary coding and debugging exercises that are so annoying are necessary because most candidates, by far, can't begin to do them -- MS:CS, real-time OS thesis project, and N years experience notwithstanding. What have these people been doing? I have seen brainteasers used well, but only as a jumping-off point for a conversation that tends well away from the puzzle. I used to use a design problem (no coding) that bright undergrads solved in two minutes, BSes in five, MSes in 20, and PhDs either never, or as fast as an undergrad. Everyone who solved it used identically the same hand gesture when describing the solution. ITA Software used to publish great programming puzzles that you were invited to solve and send with a CV. (Google bought them out and eventually took down the puzzles, back in 2010, but they might still be in wayback). To learn how your solution compared to theirs, you had to send it! It might not work so well anymore, since everything gets posted nowadays.