Coin Flip Fairness

Comments debate the randomness, biases, and probability of coin flips, including streaks, same-side tendencies, and methods for fair outcomes from biased coins, often using coin tosses as analogies for chance events.

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3,149
Comments
20
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#4010
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Keywords

e.g OP IMO HH HT NOT dicesites.com TH XOR wikipedia.org coin heads tails flip 50 probability dice 50 50 flips flipping

Sample Comments

ars • Oct 26, 2021 • View on HN

That shouldn't change anything: https://en.wikipedia.org/wiki/Fair_coin#Fair_results_from_a_...

wanderingmind • Mar 22, 2023 • View on HN

As good as flipping a coin /s

rexreed • Mar 22, 2023 • View on HN

Basically, a coin flip. Sounds like not better than chance.

IG_Semmelweiss • Jun 23, 2023 • View on HN

Flip a coin enough times, it's bound to be tails

dooglius • Dec 1, 2025 • View on HN

"fair coin" refers to both the probability of heads and tails being equal (which is still justified) as well as the trials being independent (unlikely with 100/200; more likely the "coin" is some imperfect PRNG in a loop)

supernewton • Jan 8, 2024 • View on HN

Anecdotally, with practice, some people can flip a coin to a desired outcome like 65% of the time. And .65^20 is only around 1 in 10,000.

lovemenot • Mar 23, 2021 • View on HN

Since neither heads nor tails bias had been hypothesised, 1/512 rather than 1/1024.

smt88 • Oct 19, 2021 • View on HN

Any random one, just as it's possible to flip a coin and get heads a few times in a row.

ihattendorf • Jun 3, 2022 • View on HN

Then it becomes an 80k coin toss experiment :)

anc84 • Sep 1, 2015 • View on HN

A flipped coin could have gotten that same fraction. ;)