Samuelson condition
The Samuelson condition, due to Paul Samuelson, in the theory of public economics, is a condition for optimal provision of public goods. For an economy with n consumers, the conditions is: ∑ i = 1 n MRS i = MRT {\displaystyle \sum _{i=1}^{n}{\text{MRS}}_{i}={\text{MRT}}} MRSi is individual i's marginal rate of substitution and MRT is the economy's marginal rate of transformation between the public good and an arbitrarily chosen private good.