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33 Questions

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Re: 33 Questions

#41

Post by stbullard »

Fun to think about, but in the real world, no question neatly divides people, even the gender one. To quote Reddit's u/tailcalled[1], the exo-software/meatspace world is even less standardized than the software world:

Falsehoods programmers believe about gender: http://www.cscyphers.com/blog/2012/06/28/falsehoods-programm...

Falsehoods programmers believe about names: http://www.kalzumeus.com/2010/06/17/falsehoods-programmers-b...

Falsehoods programmers believe about addresses: http://www.mjt.me.uk/posts/falsehoods-programmers-believe-ab...

Falsehoods programmers believe about time: http://infiniteundo.com/post/25326999628/falsehoods-programm...

More falsehoods programmers believe about time: http://infiniteundo.com/post/25509354022/more-falsehoods-pro...

Falsehoods programmers believe about geography: http://wiesmann.codiferes.net/wordpress/?p=15187&lang=en

[1] http://www.reddit.com/r/programming/comments/1fc147/falsehoo...

Re: 33 Questions

#42

Post by Laremere »

Assuming that the person doesn't necessarily need to know their answer (which is important for babies anyways) the answer is trivial. The first question would be "Given that we ordered all humans in order of the time of their birth, would the 1st bit of your position in the ordering be 1?", continue the other 32 questions with the remaining 32 bits.

Re: 33 Questions

#43

Post by tonyarkles »

aleprok wrote: post #31

If the goal is to have questions which can be answered only with yes or no. I don't think asking for location of the person is good thing, because there would be so many questions as there is locations. "Do you live in China, India, The United States, Indonesia, Brazil or Pakistan?" is not good question.

I'm guessing that that question is meant as a yes/no question that would divide the world population in half.

Re: 33 Questions

#44

Post by 30thElement »

deletes wrote: post #30
aroman wrote: post #25

Earlier quoted context omitted.

Well if you had conditional questions, you could ask who was born first.

That question doesn't even apply since you can only ask it to two twins, not a single person.

Going along with what someone said earlier, your last question can be "Were you born after someone who answered the previous 32 questions the same as you", which works to identify twins as well as people in general. Although I don't know how this would work for triplets (or any larger number of "twins" than 2); you'd have to make the previous 32 questions split them into groups of at most 2.

Re: 33 Questions

#45

Post by chill1 »

ronaldx wrote: post #26
psuter wrote: post #14

Interesting exercise, which I'd call impossible in the given form. Imagine someone magically came up with 32 statistically independent binary indicators. Now you need to come up with the 33th question Q such that if you pick any two persons who are similar up to the 32nd bit, that single question must allow to distinguish them. Sounds hard.

Question 33 has to split any category of people formed from the first 32 questions - very awkward, as you say. Here is a moderately-functional question 33, though: "Are you further North than any other person who has given the same answers as you for the first 32 questions?"

> "Are you further North than any other person who has given the same answers as you for the first 32 questions?"

What if one of the persons was not on the planet at the time?

Re: 33 Questions

#46

Post by fmax30 »

So you want to create a data set with entropy = 1 . Think of this in terms of a hash function , You want to create a hash which only has an address space of 33 bits. Something in terms of H(Alice) = 0x12321 {H is a function which generates 0x12321 to store the data of alice)

Doesn't this sound like perfect hashing with limited memory. I don't really think that this can be done with such memory constraints. Even now we cannot produce a perfect hash function that uses 1 bit / key. The theoretical best we can do is 1.44 bit / key. And the practical best we have done till now is 2.5 bits per key. [1]

This may just be possible without the memory constraint that is , you answer N number of questions which uniquely identify you. (where N > 48 )

[1] http://en.wikipedia.org/wiki/Perfect_hash_function#Minimal_p...

Re: 33 Questions

#47

Post by raverbashing »

stbullard wrote: post #41

Fun to think about, but in the real world, no question neatly divides people, even the gender one. To quote Reddit's u/tailcalled[1], the exo-software/meatspace world is even less standardized than the software world: Falsehoods programmers believe about gender: http://www.cscyphers.com/blog/2012/06/28/falsehoods-programm... Falsehoods programmers believe about names: http://www.kalzumeus.com/2010/06/17/falsehoods-pr…

Yes, there's so much about these.

Of course, in practice, you usually target your system to a narrow set of users at first.

But yeah, if you're facebook, or work with an airline booking system, for example, you will most likely hit every single item on these lists

Re: 33 Questions

#48

Post by measure2xcut1x »

powrtoch wrote: post #33

I don't think this problem is solvable in any elegant form, but it is solvable. You'll just end up with massively conjunctive questions that you can't even hold in your head at once, like "27: Are you a non-practicing Catholic with exactly three children, or an asian owner of a minivan produced between 1998 and 2004 that isn't green, or a licensed boat mechanic with astigmatism, or..." and so on for the next 6 pages.…

Here's my admittedly naive Sunday afternoon spitball on an elegant solution:

I like the idea of a human UUID/GUID type identifier.

I would also like to think that this is solvable using strictly biological and physical properties, sampled at birth.

Otherwise, time and culture factors would seem make it difficult to produce a static set of "apples to apples" questions and answers.

I wonder if the right maths applied to existing genetic and forensics big data sets could produce the 33 questions.

Re: 33 Questions

#50

Post by unfamiliar »

Are you male? This will not split the population 50/50. One group will be slightly larger, and you then only have 32 questions to subdivide this larger group into further categories which is impossible.

This is not possible unless the categories _precisely_ bisect the group each time.

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