Is there such a thing as a substantial external model?

Field of economics

Explanation:

Substance Modeling occurs in economics, it is a model based on positive externalities of production. As the government grant subsidies to producers of goods and services that increase demand side, so it expresses in terms of some net loss/ gain of services if taking the example of a university in terms of education level achievement and attendance at schools, etc.

landlessness of ordinary people

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