One standard for measuring service aboard cruise ships is the crew-to-passenger ratio. Theoretically, the more attractive the ratio (i.e., the more crew serving a single passenger), the better the service. It stands to reason that luxury ships would have the most attractive crew-to-passenger ratios, followed by premium category ships and mass market ships.
Crew-to-passenger ratio is derived from dividing the number of passengers by the number of crew. The math is tricky, and the ratios can be misleading, because cruise ships list two numbers for passenger capacity. The first represents capacity with all lower beds filled (essentially, this means double occupancy). But some staterooms have four beds, and so the second number represents capacity when all beds are filled.
But crew-to-passenger ratios do not tell the whole story. New technology makes ship operations more efficient, requiring fewer crew members to perform tasks.