The allocator was an artificial intelligence program created by the Jye, a humanoid Delta Quadrant species known for their administrative abilities. Health care was rationed by the allocator and was divided into several levels designated by colors (level red, level blue, level white, etc.). Each person on, or visiting, Dinaal was assigned a treatment coefficient, or TC, a number which determined the amount of medical treatment and medication a person received, based on how useful a person is to society, not how badly they needed it.
Chellick was the Jye administrator of Hospital Ship 4-2 on Dinaal. He was brought in to help the Dinaali who were plagued with natural disasters and famine. He used an allocator computer to determine who would live and who would die. The treatment was assigned according to the treatment coefficient. (VOY: "Critical Care")