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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

#81
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…

[deleted]

Re: Steve Ballmer's incorrect binary search interview question

#82
post #40
post #17

Earlier quoted context omitted.

Although Ballmer could still be incorrect, because a 'sufficiently logical' player would also presumably know that he could pick numbers that'll be the most difficult to find via binary-search, so by the same logic you could also meta-game it, and assume any number that can be found in 5 steps with a binary search is immediately out. This would narrow the search space to only 37 numbers, which can then easily be foun…

There isn't much of metagame if number is only in Ballmers mind. No matter what guesses you choose he can force you to make at least log_2(100) guesses. Doing anything except splitting in half will only increase amount of guesses. There are two things that can change the game, requiring Baller to write the number on a piece of paper before the start. Other thing you could do is writing a number on piece of paper your…

This assumes Ballmer is cheating, rather than just behaving adversarially but within the rules.

If we accept cheating is allowed, we can also potentially accept other 'cheating' scenarios where the player repeatedly punches Ballmer in the face until he discloses the number, thus winning. Or where the player just refuses to pay at the end.

IMO the problem is only interesting if we assume any form of cheating isn't allowed.

Re: Steve Ballmer's incorrect binary search interview question

#83
post #22

Earlier quoted context omitted.

And then if Ballmer assumes the other party assumes he's being adversarial we get into game theory.

The ultimate conclusion of which is likely that both parties will decay to picking the secret value/first guess randomly (although I'm not sure if the optimal distribution is perfectly flat?), which is also something that we can model.

Seems like the distribution definitely won’t be flat since the guesser can randomly choose any of the numbers from 37 to 64 as a first guess without losing anything on the large side, so Ballmer starting with any of those increases his chance of having to pay out the $5. Likewise for other numbers there are nuances to what can be guessed.

Re: Steve Ballmer's incorrect binary search interview question

#84
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…

And then if Ballmer assumes the other party assumes he's being adversarial we get into game theory.

So the actual problem here is to find Nash equilibrium.

Re: Steve Ballmer's incorrect binary search interview question

#85
post #76

Earlier quoted context omitted.

One of the worst interviews I ever had was just like that. Often times, the "gotcha" part is just dumb and nonsensical, yet gives the interviewer(s) a sense of misguided (false) superiority, and wastes everyone's time. I would venture to say that 99% of the time it's complete un-indicative of how effective the candidate would be in the role. Referring to my aforementioned bad interview - the question, after all the t…

Great interview from a certain perspective. You knew for sure (if you had a choice) that you didn't want to work for this specific person.

[deleted]

Re: Steve Ballmer's incorrect binary search interview question

#86
post #76
post #52

Earlier quoted context omitted.

What was the last time you were on the interview? I think like 70% of interviews I ever had were like they were there to prove how smart they are and how stupid I am. I suppose most likely to make me feel stupid and accept lowball offer.

One of the worst interviews I ever had was just like that. Often times, the "gotcha" part is just dumb and nonsensical, yet gives the interviewer(s) a sense of misguided (false) superiority, and wastes everyone's time. I would venture to say that 99% of the time it's complete un-indicative of how effective the candidate would be in the role. Referring to my aforementioned bad interview - the question, after all the t…

> How on earth does that indicate if a junior frontend dev can do their job or not?

Playing devil's advocate, maybe a junior frontend dev that doesn't trust that they understand what someone is asking for and pushes back on bits that should be obvious will perform better (in some contexts?) than one that doesn't.

For a junior role in particular, though, it really doesn't seem like that should be the threshold and it sounds like it was delivered poorly on top of that.

Re: Steve Ballmer's incorrect binary search interview question

#87
post #76
post #52

Earlier quoted context omitted.

What was the last time you were on the interview? I think like 70% of interviews I ever had were like they were there to prove how smart they are and how stupid I am. I suppose most likely to make me feel stupid and accept lowball offer.

One of the worst interviews I ever had was just like that. Often times, the "gotcha" part is just dumb and nonsensical, yet gives the interviewer(s) a sense of misguided (false) superiority, and wastes everyone's time. I would venture to say that 99% of the time it's complete un-indicative of how effective the candidate would be in the role. Referring to my aforementioned bad interview - the question, after all the t…

That just feels like playing chess with a pigeon

Re: Steve Ballmer's incorrect binary search interview question

#88
post #82
post #40

Earlier quoted context omitted.

There isn't much of metagame if number is only in Ballmers mind. No matter what guesses you choose he can force you to make at least log_2(100) guesses. Doing anything except splitting in half will only increase amount of guesses. There are two things that can change the game, requiring Baller to write the number on a piece of paper before the start. Other thing you could do is writing a number on piece of paper your…

This assumes Ballmer is cheating, rather than just behaving adversarially but within the rules. If we accept cheating is allowed, we can also potentially accept other 'cheating' scenarios where the player repeatedly punches Ballmer in the face until he discloses the number, thus winning. Or where the player just refuses to pay at the end. IMO the problem is only interesting if we assume any form of cheating isn't all…

Do you want to catch a chair to the side of the head? Because this is how you catch a chair to the side of the head.

Re: Steve Ballmer's incorrect binary search interview question

#89

Is there a name for the fallacy where you attribute your success in life to your own intelligence, and thus assume that you are smarter than everyone else, and that you therefor must be right about everything? Sort of an opposite impostor syndrome?

Fundamental attribution error https://en.wikipedia.org/wiki/Fundamental_attribution_error

Re: Steve Ballmer's incorrect binary search interview question

#90
post #52

Earlier quoted context omitted.

What was the last time you were on the interview? I think like 70% of interviews I ever had were like they were there to prove how smart they are and how stupid I am. I suppose most likely to make me feel stupid and accept lowball offer.

Like this one: https://rachelbythebay.com/w/2011/07/27/ohreally/ Yes, that happens, and elsewhere she goes on about culture in tech.

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 in more detail, but it seems like she just threw out SNMP as misleading bait, and he maybe mixed up ICMP and SNMP. She is right to call herself a troll, but wow, that's crazy to say she caught the guy in a lie of insanity.

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