Flipped coins found not to be as fair as thought

The researchers found that Diaconis was right—there was a slight bias. They found the coin landed with the same side up as when it was launched 50.8% of the time. […]

The team concludes that while the bias they found is slight, it could be meaningful if multiple coin tosses are used to determine an outcome—for example, flipping a quarter 1,000 times and betting $1 each time (with winnings of 0 or 2$ each round) should result in an average overall win of $19.

Perhaps a (ahem) chance for @jamesthomson@mastodon.social’s unbiased(?) Dice by PCalc.