Refers to the number of all the output buffer variable factors to increase another 1 unit to determine whether the increase in variable factors, each unit will affect the increase of productivity.
Represents the total output increased by 1 unit for variable factor to know. The increase in each variable factor will affect the increase of productivity.
Mean number of total output increases when slack variable factor again 1 units, in order to know The rise of variable factor each unit will result in how to increase yield.