Instrumental variables

The following text is drawn from the World Bank's website.

Instrumental variables

Instrumental Variables is a technique that identifies a factor that determines receipt of a project, but which does not influence outcomes of interest. This factor is then used to simulate who would have been in the treatment group, and who would have been in the control group if receipt of the project was based on that factor. The difference in outcomes between these simulated treatment and control groups is then the impact of the project.


Source: The World Bank http://go.worldbank.org/J35S3J8B60