While traditionally thought to be 50/50, recent research suggests that a flipped coin might not be truly fair.
A team of researchers at the University of Amsterdam, led by Frantisek Bartos, conducted a study involving over 350,000 coin flips and found that coins tend to land on the same side they started on with a slight bias.
Specifically, their findings indicate a 50.8% chance of the coin landing on the side that was initially facing upwards.
This bias isn’t related to the coin itself, but rather the way it’s flipped. The slight wobble introduced by the human flipper causes the coin to spend a bit more time with its starting side facing upwards, increasing the likelihood of it landing on that side.
So, while the difference might seem small, it means that a standard coin toss is not perfectly random and carries a slight advantage for the side that begins facing up.
Is it true that a coin flip is 51/49?
The coin exhibits a very simple kind of dependence between its successive states—namely, it has a 51 percent chance of staying in the same state it was in (heads or tails), and a 49 percent chance that it will switch to the opposite state.
Is flipping a coin truly random?
He found that caught coins have a slight tendency to end up in the same state as they were when initially tossed. The bias is, however, incredibly slight. So the outcome of tossing a coin can indeed be seen as random – whether it’s caught in mid-air, or allowed to bounce.