Fewer prisoners, prostitutes and pimps are showing up among the Cuban refugees landing in South Florida, immigration officials said yesterday.

The officials said they are beginning to see a larger proportion of families in the tide of refugees that washes up each day.

"We're getting a better mix," an immigration officer said. They had been concerned that a large number of the refugees were coming from Cuban jails.

Army troops arrived in Miami yesterday with C-rations and equipment to care for refugees at 14 processing centers, and Marines prepared to take over operations in Key West. Both services were to replace the Florida National Guard.

Gov. Bob Graham said the state has spent $300,000 on food, medicine, security and transportation.

About 3,000 Cubans landed in Key West yesterday, lifting the total to more than 30,000.

Meanwhile in Lake Placid, N.Y., a federal official inspected the Olympic Village that housed athletes during the recent winter games to determine if it could be used to house Cuban refugees.

Roy Newsome of the Emergency Management Agency toured the site in nearby Raybrook, which eventually is to be a medium-security federal prison for about 500 inmates.

His agency is inspecting smaller sites such as the Olympic Village, Newsome said, to house special groups such as families or persons wishing to relocate in a specific geographic area.

Newsome said plans called for housing the refugees for up to 120 days to allow them time to obtain sponsors. They would then move to the sponsors' home community.