Researchers used coins from 46 currencies to test their theory.
Scientists Tossed 350,757 Coins To Prove The Theory That Coin Tosses Aren't 50/50
I've never really been big on gambling, but if there's one thing I'd wager on, it's that 50/50 odds seem pretty fair.
It feels like a balanced game of chance, right? Whether you win or lose seems evenly split.
That's why a lot of folks lean on those 50/50 odds for making all kinds of choices, like figuring out whose turn it is to take the garbage out.
A coin flip is a classic go-to for these decisions, based on the assumption that there's an equal shot for the coin to come up 'heads' or 'tails'.

But, believe it or not, it turns out that's not exactly how it works.
And no, this isn't about the old 'heads I win, tails you lose' trick.
This insight comes from a study where the results of 350,757 coin flips were carefully documented.
This study uncovered a slight, but present, bias in every coin flip.
Involving 48 participants, the research team had them flip coins from 46 different types of currency, accumulating to 350,757 flips.
What they discovered was that there's a 50.8 percent chance a coin will land on the same face it started on.
This finding is based on what's known as the Diaconis Model.

According to this model, and the researchers' interpretation, a coin is somewhat more inclined to end up on the side it was initially placed on when flipped.
The reason?
"According to the Diaconis model, precession causes the coin to spend more time in the air with the initial side facing up."
"Consequently, the coin has a higher chance of landing on the same side as it started (i.e., 'same-side bias')."
So, essentially, because the coin spends more airtime showing the face it began with, there's a slight lean towards that side.
To bring these findings closer to home, the researchers laid out a hypothetical betting scenario: "The magnitude of the observed bias can be illustrated using a betting scenario."
"If you bet a dollar on the outcome of a coin toss (i.e., paying 1 dollar to enter, and winning either 0 or 2 dollars depending on the outcome) and repeat the bet 1,000 times, knowing the starting position of the coin toss would earn you 19 dollars on average."
"This is more than the casino advantage for six-deck blackjack against an optimal-strategy player, where the casino would make $5 on a comparable bet, but less than the casino advantage for single-zero roulette, where the casino would make $27 on average."
So, armed with this little tidbit, maybe it's time to challenge a friend to a coin toss and test if the odds really do lean in your favor.