A gambler’s fallacy is a heuristic in which a person thinks the probability of an outcome has changed, when in reality, it has stayed the same. If a coin is flipped 10 times and lands on “heads” everytime, a person employing gambler’s fallacy would believe the probability of the coin landing on “heads” the 11th time would be very low. The truth, however, is that the probability of a coin being “heads” or “tails” is 50% everytime the coin is flipped. The probability remains the same.