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by addisonl 70 days ago
> Question: A fair die rolling a 6 twice in a row is more likely than rolling 1-2-3-4-5-6 in sequence

Two 6s in a row is 1/36 chance (1/6)^2

1-2-3-4-5-6 is a 1/46656 chance (1/6)^6

Website is claiming they are the same probability:

> Same probability: 1/46,656 — Both outcomes have exactly the same probability: (1/6)^6 = 1/46,656. This illustrates the representativeness heuristic — random-looking sequences feel more probable than ordered ones.

Website's "answer" is wrong: was the question supposed to be rolling a 6 six times in a row?

4 comments

Yeah, most likely it was try to identify a bias of human perception, that 1,2,3,4,5,6 would be more probably than 6x6.

A better way to illustrate this bias is with coin flips. People will tell you that odds of 6 heads is more rare than the odds 3 tails then 3 heads. The difficulty is understanding whether they mean "in order" or "as a group".

If it's in order, the odds are the same. Every order of H/T has the same probability, but humans will see "all heads" and think that's more rare. But the important bit is whether there's a clear understanding ordering.

That's definitely better framing for this question. Much cleaner way to illustrate that point!
You're right, that's a mistake in how I phrased the question. It should say "six times in a row" not "twice in a row". Fixing it now! Thanks for pointing that out!
If anyone is interested in why we are bad at estimating, please check out the amazing book Thinking, Fast and Slow: Daniel Kahneman.
Great recommendation. That was one of the biggest influences for starting to write my decisions down and then building this.
came with the same complaint. the website then had the nerve to tell me i am overconfident.
Fair point! Bad question on my end. The overconfidence was based on all 10 questions though, not just that one!