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Steve Ballmer's incorrect binary search interview question

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Re: Steve Ballmer's incorrect binary search interview question

#151
post #6

I'm so glad I've managed my career such that I've never had to answer bullshit interview questions like this. The only purpose of these is to stroke the asker's ego, they tell you nothing at all about the candidate. What a waste of time.

Same. I don't know if I have been lucky. I have worked with 6 companies in the past (startups, multinationals, consultancy companies, etc.) and I have never had to answer brain teasers.

Re: Steve Ballmer's incorrect binary search interview question

#152

Earlier quoted context omitted.

Is the guy's response really that far off? Each router checks its table for the destination, and if it doesn't know it, queries the next upstream router, its default route, the next hop. Each router likely ultimately informs you of the hand-off via a packet of some sort, and your then traceroute sends a ping/ICMP to each hop to learn how far away they are. He maybe could've been pushed to expand on what he did know i…

Is the guy's response really that far off? When you think about it, the candidate isn't even that wrong. Back then, at university, a certain professor would explain the oral exam to the candidate at the beginning. He would explain that he would incrementally increase the difficulty and skip from area to area. The goal would be to find the limits of the student's knowledge, the student would walk away feeling terrible…

Downvoted for jumping from legitimate criticism of her interview methodology to very personal and completely baseless accusations. This is not the internet I want to live in.

Re: Steve Ballmer's incorrect binary search interview question

#153

Earlier quoted context omitted.

That SME guy sounds like an asshole, but I used to have an interview technique where I’d ask increasingly specific and low level questions about the candidates area of expertise until it got to the point where I’d be pretty confident they wouldn’t know the answer off the top of their head. I wasn’t adversarial or rude about it, I just wanted to find out if they were comfortable saying “I don’t know”, because not know…

I always say I don’t know in interviews when I really don’t, rather than try to bluff. Some interviewers don’t like this though. As with the parent, perhaps that’s actually a good thing as you avoid having to work in a bad environment. Other times though, you may be being interviewed with a bad egg who you’ll never actually need to work with in the actual job.

Yeah this is basically how I see it, there’s a natural selection to it. If you practice deceit and politicking in interviews (and in the office), you’ll select yourself into, and only be able to succeed in organisations that value those things. If you practice honesty and candor in interviews, then you’ll expect the same (over time at least). In interviews I think you should just be guided by your genuine values and be yourself (well, whatever version of yourself you feel most comfortable bringing to the office every day). It probably doesn’t maximise job offer conversions, but in my experience it maximises being in working environments that I’m most likely to enjoy and fit into well.

Edit: By honesty in interviews, I mean to a point. There’s some things you absolutely should lie about in interviews (if you’re confident you can get away with it). For instance “what’s your current salary” is a great question to lie about, that they really have no business asking anyway.

Re: Steve Ballmer's incorrect binary search interview question

#154
post #29

"Should you accept to play this game?" Absolutely yes. I like games. The purpose of games is to have fun. This seems like a fun game for like the first $20, a sum I can afford to play a fun game for 10 minutes. Then at the end, I get to say "I once lost $20 to Steve Balmer playing binary search", which is a fun sentence I can dine out on, and is worth more than $20 to me. I feel like perhaps this is why MS under Balm…

I don't know why you'd make this comment... I find it hard to believe you're actually stupid enough to not understand the implicit "(i.e. is your expected profit greater than 0)". If you answered like this in an interview I would definitely not give you the job. I did actually interview someone once who was like this - "How would you do this?" "Well you shouldn't do it. I think you should do this other thing.". He di…

I would be concerned if senior stuff wouldn’t speak up and bring up possible technical issues. That’s like half of their value.

Re: Steve Ballmer's incorrect binary search interview question

#155
post #10

The article implies that the interviewee assumes that the number is being chosen randomly, when Ballmer could actually be choosing adversarially. However, if the interviewee assumes that Ballmer is being adversarial, then you can pick a different value as your initial guess, which causes the probabilities to shift. Even the OP assumes that the interviewee will start guessing with 50, but, because of the way binary se…

I'm not really married to this idea, but my first reaction is that to assume a random number would be an invalid assumption.

The scenario is framed as a zero sum game: one of us wins. The question is, "should you play?"

In order to answer, you need to be able to determine whether or not there is an optimal strategy that is generally successful.That should include both the assumption that Ballmer has chosen a number adversarial weighed against the random choice.

Re: Steve Ballmer's incorrect binary search interview question

#156
I really am curious about the Nash equilibrium solution. I assume that as a commenter has mentioned, for the guesser it involves returning random numbers near the binary search. But I’m curious if for the picker it involves a uniform or non uniform initial distribution?? I’m sure someone on HN knows/can explain?

Re: Steve Ballmer's incorrect binary search interview question

#157
post #8

The (TV) interview is kind of funny because the journalist asks him, after he goes through the idiotic song and dance of this brain teaser: "so what did you learn about me?" This is actually a very insightful question. What did you learn, Mr Ballmer? To which he literally has no answer: "I learned you need to step back and really ask if you're going to make money on this thing".. uh, okay Steve. Cool. Thanks for your…

He was being polite and understanding. They aren’t in a job interview setting, it’s not a correct frame to judge. But if it were, she would totally fail with that attitude of not thinking through the problem. That’s what his comment about stepping back meant.

Re: Steve Ballmer's incorrect binary search interview question

#158

I wrote similar code to show that as long as you choose your starting number randomly you will have positive EV. Not sure how they kept using this interview question without realizing this. https://x.com/sampullara/status/1810088483425558630

I think they were using it just fine because they don’t say or in any way imply that the choice is random.

Re: Steve Ballmer's incorrect binary search interview question

#159
post #111
post #100

Earlier quoted context omitted.

If Ballmer is being adversarial, he won’t pick the number at the start, and always win. Of course you can set up the game such that Ballmer has to commit on a number at the start of the game (by sealing it in an envelope or whatever), but that wasn’t specified.

Ballmer opens with "I'm thinking of a number between 1 and 100". If he uses your strategy instead that's a different scenario.

That’s only if you’re willing to trust Ballmer to do what he claims, which I wouldn’t.

Re: Steve Ballmer's incorrect binary search interview question

#160

I recently interviewed for a senior level role for a complex domain (payments), this is an area I have more than a decade of experience. The interviews went flawlessly because I know payments inside out, not just in US but in UK and most EU jurisdictions. The funny bit is that the role being senior, influencing, soft communication skills and managing conflict are even more important than the subject matter expertise…

> they threw an obnoxious senior manager that kept interrupting me as I calmly answered the questions This is a red flag. To me this signals that a company not only has a toxic culture, but embraces it. Such places attract personalities who love conflict and once there are enough people, they set the culture. What doesn't get said often is that conflict is a failure of leadership. Often all it takes to resolve confli…

Personally, I don't like this kind of thinking that it's a failure of leadership first and foremost. Yes, of course leadership can both work proactively to prevent conflict, as well as try to minimize/react to situations. But, what about the conflicting people? Shouldn't they (in most situations), bear the most responsibility to not end up/turn a situation into a conflict? Sometimes I get afraid of comments that (in my interpretation) imply that basically everything bad that happens is the fault of leadership (management). To me that breeds a culture where ICs are taught to not own their situation, which I believe is very very dangerous (to everyone involved).

Maybe I'm just interpreting your comment wrong :)

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