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A comment on Ask HN: What have you found the worst interview question to be?. Parent comment

Re:Ask HN: What have you found the worst interview question ... by ansy on Tuesday February 05, 2019 @06:49AM (#19084471)
Regarding the first question, fundamentally you can’t “prove” a number is truly random. Even if a number or sequence is completely not random looking (e.g. a valid copy of Windows 98), there is a chance it really is random and coincidental. You could have immediately said that. Did you?

But, given that this was a front end job, a common way to visually test the quality of a pseudo-random number generator is to generate a series of numbers and plot the results with pixels visually[1]. If the PRNG is high quality you’ll get a nice even static field. If there is a bias it will show up as a gradient or pattern in the pixels. I suspect this is actually what the interviewer was after.

[1] http://judeokelly.com/simple-visual-random-number-test/

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Re:Ask HN: What have you found the worst interview question ... by seattle_spring on Tuesday February 05, 2019 @12:08PM (#19087229)
That was literally my first guess, and he flatly said it was wrong and not reliable, and to try again. I'm not joking here.
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