A lottery is an arrangement in which prizes are allocated to a class of individuals in a manner that depends entirely on chance. It may involve a fixed amount of cash or goods, or it can be in the form of a percentage of ticket sales. Often, a person can buy tickets in groups, which increases the chance of winning but reduces each individual’s payout.

Lotteries have a long history, dating back centuries to the Roman Empire, when they were used as an amusement at dinner parties. Prizes were usually fancy items, such as dinnerware. More recently, they have been used by governments to raise funds for infrastructure and other public goods.

People in the bottom quintile of incomes, those living on $24,000 or less a year, spend a significant portion of their money on lottery tickets. While that’s regressive, it also makes sense. These folks don’t have a lot of discretionary income left over, and they probably feel that they can’t afford to save up for something big.

Lotteries are a great way to give these people hope. Despite the odds of winning, they know that someone in their group will hit the jackpot. And even if that doesn’t happen, they can enjoy the entertainment value of playing, or the non-monetary utility of dreaming about it. It’s this hope, irrational as it is, that lottery organizers focus on emphasizing, because it obscures the regressivity of the arrangement. And it may help explain why the lottery is so popular.