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33 Questions

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Re: 33 Questions

#61

Post by Serplat »

Houshalter wrote: post #51
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.…

Those are bad examples because those questions don't split the population in two. Very few people are non-practicing Catholics with exactly three children. If you want to limit the number of questions to just 33 then you have to choose your questions very carefully.

I think you misunderstood. powrtoch proposed having a set of questions in which each individual question is itself very complicated. For example, being a non-practicing Catholic with exactly three children is only one small facet to a single question. By or'ing a bunch of really specific questions together you can come very close to getting exactly 50% of the population to answer yes to a single question.

Re: 33 Questions

#62

Post by rattray »

This is a fun exercise, but as others have pointed out likely impossible in its current form.

We don't have true constraints on space though; why limit to 33 bits? How could we still provide a meaningful UUID to each person?

A UUID based on time and location of birth might be more feasible than any other approach, since neither will change and it's the least likely to be ambiguous. Capturing UTC at the time of cutting or otherwise removing the umbilical cord could be one way of choosing as precise, non-debatable a timestamp as any. Adding lat/long and, say, the first byte of the UTF-8 character of the mother's name (or an aspect of the mother's UUID?) could get you the rest of the way there.

Of course, this falls over in places without access to precise timing and geolocation.

Re: 33 Questions

#63

Post by edelans »

rattray wrote: post #62

This is a fun exercise, but as others have pointed out likely impossible in its current form. We don't have true constraints on space though; why limit to 33 bits? How could we still provide a meaningful UUID to each person? A UUID based on time and location of birth might be more feasible than any other approach, since neither will change and it's the least likely to be ambiguous. Capturing UTC at the time of cuttin…

I think the limitation to 33 bits is because this is the smallest power of 2 which is higher than the world's population:

2^32 = 4.29 billions,

2^33 = 8.58 billions,

2^34 = 17 billions,

Re: 33 Questions

#64

Post by [deleted] »

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…

[deleted]

Re: 33 Questions

#66

Post by Accredified »

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?"

Just make questions 33 be the your assigned number then. 0 or 1

Re: 33 Questions

#67

Post by r0muald »

rattray wrote: post #62

This is a fun exercise, but as others have pointed out likely impossible in its current form. We don't have true constraints on space though; why limit to 33 bits? How could we still provide a meaningful UUID to each person? A UUID based on time and location of birth might be more feasible than any other approach, since neither will change and it's the least likely to be ambiguous. Capturing UTC at the time of cuttin…

Another pitfall of this thought-experiment is that there is no room for the constant number of humans who die and are born every day: the set of 33 questions hypothetical questions of today will not be valid tomorrow.

Re: 33 Questions

#68

Post by mds »

Serplat wrote: post #61
Houshalter wrote: post #51

Earlier quoted context omitted.

Those are bad examples because those questions don't split the population in two. Very few people are non-practicing Catholics with exactly three children. If you want to limit the number of questions to just 33 then you have to choose your questions very carefully.

I think you misunderstood. powrtoch proposed having a set of questions in which each individual question is itself very complicated. For example, being a non-practicing Catholic with exactly three children is only one small facet to a single question. By or'ing a bunch of really specific questions together you can come very close to getting exactly 50% of the population to answer yes to a single question.

That's kinda cheating though isn't it? Like chaining a dozen statements on one line with semicolons and going, "look I can write that program in one line!"

Re: 33 Questions

#69

Post by abentspoon »

It's not enough to find 33 independent questions that evenly split the world's population.

An optimal, though inelegant solution to that goal might look something like this:

"Is the {1..33}th bit of sha1(name : location : date of birth) 1?".

Clearly you'll have tons of collisions with that solution, as you would have with any solution using 33 independent questions.

To uniquely identify people, we'd either need to use more bits, or look very closely at the population and derive very specific questions.

Re: 33 Questions

#70

Post by ghostdiver »

measure2xcut1x wrote: post #48
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 t…

DNA is your UUID/GUID
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