In this article, the author investigates the randomness of xkcd’s “random” button. They explain that randomness is important in things like cryptography and there are several ways to test the randomness of a random number generator. The author used the NIST Statistical Test Suite to test 10,000 xkcd-random numbers and found that they all passed the tests, proving that xkcd’s random generator is reasonably unpredictable and unbiased. The author also explores human nature and mathematical explanations for why the random number generation may appear biased to users. They provide an explanation for why hitting the random button may result in repeat comics and use the birthday problem to calculate the probability of seeing a duplicate comic after a certain number of clicks. Overall, the article demonstrates the complexity of randomness and how statistical facts can sometimes trick us into seeing patterns that aren’t actually there.
https://hardmath123.github.io/xkcd-random.html