Specification (regression)

In regression analysis specification is the process of developing a regression model. This process consists of selecting an appropriate functional form for the model and choosing which variables to include. For instance, one may specify the functional relationship ${\displaystyle y=f(s,x)}$ between personal income ${\displaystyle y}$ and human capital in terms of schooling ${\displaystyle s}$ and on-the-job experience ${\displaystyle x}$ as:

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