THE ASPECT OF gambling that has caused the most recent controversy is the question "Who is doing the gambling"" Researchers have conducted demographic studies to determine what sort of people gamble most frequently, and their findings are troublesome to both critics and supporters of gambling in the United States.

Who gambles"

One of the most interesting findings of the studies is that most gambling is being done by a very small part of the population. In a 1998 study of lottery ticket sales, for example, Duke University professors Charles Clotfelter and Phillip Cook found that although a wide variety of people buy lottery tickets, 5 percent of lottery players actually account for 51 percent of the ticket sales.

They also discovered that the most frequent players are households that earn less than $10,000 a year. Says Cook, "The sense that everybody plays...