From the paper linked above: one cannot, for example, weight a coin so that it is substantially more likely to land “heads” than “tails” when flipped and caugh

From the paper linked above: one cannot, for example, weight a coin so that it is substantially more likely to land “heads” than “tails” when flipped and caught in the hand in the usual manner. Coin tosses can be biased only if the coin is allowed to bounce or be spun rather than simply flipped in the air.