A system for determining a state of compaction of a work material includes a roller having a vibration system. A controller is configured to determine the speed of the machine, determine an inclination of the machine, and determine an inclination power change based upon the inclination and the speed of the machine. The controller is also configured to determine the gross power loss resulting from the compaction operation, determine a vibration compensation factor based upon vibration characteristics of the vibration system, and determine the state of compaction of the work material based upon the inclination power change, the power loss, and the vibration compensation factor.