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People familiar with unit testing and test driven development will feel at home with this kind of puzzle. That doesn't mean that they will be less biased in soc
by veli_joza 11y ago
People familiar with unit testing and test driven development will feel at home with this kind of puzzle. That doesn't mean that they will be less biased in social/political decisions, it just means that this test will fail to prove a point.
- ttctciyf 11y agoHah :) Seriously, though, it seems a bit of leap from the existence of confirmation bias to explaining away the public outpourings of US Politicians about their financial crises and foreign policy disasters - in the absence of better data as to just why the given statements were made ascribing this to confirmation bias seems itself open to accusations of confirmation bias! :)
- diminishedprime 11y agoThat's exactly what I was thinking. I (sometimes) follow TDD, and I applied it to this problem. I made sure to include negatives, 0, positives, and include primes here or there to help avoid issues with multiplication/exponentiation. After a few of these, I felt pretty confident that the rule was simple.
- ubernostrum 11y agoMy process was: [3 5 7] [7 5 3] [8 4 2] [5 7 3] [1 2 3] [1 1 1] [0 1 2] At that point I could've done some more to be really certain, but felt confident enough and guessed (correctly).
- jonkiddy 11y ago[16 32 64] [0 0 0] [1 2 3] [3 2 1] [-1 0 1] [3 5 7] [-2 -1 0] [111 54231 9999999999999999999999] At that point, I correctly answered the question.
- jws 11y agoSimilar to mine, but we both actually failed. Real numbers are accepted and we did not test that.
- WildUtah 11y agoIt accepts floating point numbers. To approximately double precision. But it accepts zero percent of real numbers.
- eru 11y agoI can nitpick better than that! To talk about a certain fraction of real numbers you have to have a distribution over them. In general we take the uniform distribution if no distribution is explicitly given. That doesn't work for real numbers (it doesn't even work for natural numbers). (See https://math.stackexchange.com/questions/14777/why-isnt-there-a-uniform-probability-distribution-over-the-positive-real-number https://math.stackexchange.com/questions/14777/why-isnt-ther...) If there's no implicit default distribution, we have to pick on. I can pick one where they cover an arbitrary high percentage of real numbers..
- elnion 11y agoDown the rabbit hole of pedantry: we don't need a distribution, just a measure, if we want to talk about how many reals it accepts. The Lebesgue measure is implied on the Reals if none is given, and the computable reals have measure zero. We can't reasonably talk about a percent coverage, since the Lebesgue measure of the reals is infinite, but as a non-technical description, 'zero percent' is morally equivalent to saying it only covers a measure-zero set.
- profinger 11y agoI did this plus also testing [1 1.5 2]
- perlgeek 11y agoSo you limited yourself to non-negative integers, and had no idea what negative numbers or fractions would do.
- eli 11y agoBased on the context of the question and the UI of the testing interface, fractions seem unlikely to be an intended part of the question. I likewise wouldn't bother testing unicode U+216x roman numerals.
- Ntrails 11y agoIt refused to accept both fractions and imaginary numbers. I did test negatives and zeros since that was really the only remaining set I could think of. Most importantly I used about 6 tests (3 right 3 wrong) to come up with the answer and then did another 17 looking for the trick. After all, it couldn't just be that simple right?
- bbcbasic 11y agoAlso he didn't know what numbers whose digits add up to 88 would do.
- __david__ 11y agoTheir input on the phone wouldn't allow minus or period characters so I assumed positive integers were the set.
- ubernostrum 11y agoThe presentation of the problem -- and I know that trusting the problem state is unwise sometimes in cognitive-bias tests, since many such tests are actually designed to be "we said we were asking X but actually meant Y" -- indicated a simple rule, rather than one which would behave differently on different classes of numbers. So after the tests listed above I felt confident enough to guess.
- joezydeco 11y agoDid you try floating point numbers? I didn't see anything in the text that said integers only.
- tptacek 11y agoI tried floating point numbers. Also, at 28 decimal places, the test breaks; it's not arbitrary precision. So, technically, the answer isn't simply "any ascending sequence of numbers".
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- SiVal 11y agoI actually avoided going that far to avoid getting bad data. I was trying to answer the question, "What does the experimenter THINK his rule is?" rather than what will the computer do. Since the computer can't be infinite, it will inevitably fail with overflow, underflow, and such. I was relieved, in fact, when it worked with negatives and floats in a "safe" range. I also tested with 1,1,2 and 1,2,2 to make sure that the required increase applied to ALL of the values, not just a specific pair.
- mjevans 11y agoI too tried to test if it was only one pair that was significant. However I grew impatient and didn't try to come up with more tests when I thought I had a sufficient answer to explain my most vexing observation (negative, positive, positive out of combinations involving negative numbers). The observation to brainstorm for ways of proving that a statement is in fact wrong, and exhausting them, is such an eloquent way of wording the hunt for a negative.
- joezydeco 11y agoHah! Nice catch.
- 11y ago
- rahimnathwani 11y agoI was a little less systematic, but still had a positive:negative ratio of 1:2 before I submitted my answer. 4,6,8 Y 1,1,1 N 1,2,3 Y 1,6666,8777 Y 1,0,1 N 3,2,1 N 3,2,3 N 5,6,4 N 7,5,6 N
- benihana 11y agoI was just writing this out! I believe practice in unit testing is what let me get this question right. I almost submitted n^1, n^2, n^3 before I realized I didn't get any wrong answers and something didn't feel right. I credit this 'instinct' to having written thousands of tests, and trying to make them fail to make sure my tests weren't lying to me.
- LoSboccacc 11y agogot tricked even if I tested 1, 1, 1
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- tjohns 11y ago1, 1, 1 was actually the test case that clued me in that n^1, n^2, n^3 couldn't be the right solution.
- tikhonj 11y agoI mean, it also illustrates how training and systematic reasoning can improve these things. Whether explicitly or implicitly, I picked up certain skills and procedures for problem solving (from programming and math contests) that I now use by default. Trying a bunch of examples, coming up with a hypothesis, trying to disprove it, testing edge cases… This doesn't mean I always use these—at the very least, I have to explicitly jump into "problem solving" mode—but it means they can be useful. It's still a meaningful difference, and could very well apply to lots of things beyond this kind of puzzle.
- aptwebapps 11y agoExactly. I'm just as 'No' averse as the next person but the 'No' I'm averse to is the one where you make wrong assumptions and it comes back to haunt you afterwards.