The so-called shadow wage refers to the price paid by the society for the use of labor in the project. It is included in the operating cost adjusted according to economic value. It reflects the original interests abandoned by the society because the labor force is used in the proposed project, and is composed of the marginal output of the labor force and the consumption of social resources caused by the employment or transfer of the labor force.

Shadow price was first put forward by the Dutch economist Jan Dingbergen in the late 1930s. It was calculated by the mathematical method of linear programming and reflected the optimal allocation of social resources.

The so-called shadow exchange rate refers to the exchange rate that can correctly reflect the true value of foreign exchange, that is, the shadow price of foreign exchange.