Instrumental variables

Identifying causal impacts is central to educational research and policy analysis. There are many techniques that can help researchers identify causal impacts including instrumental variables estimation – the focus of this article. This article provides a simple overview of instrumental variables, its key assumptions, and its potential to produce unbiased estimates. The article also demonstrates several examples of how instrumental variables estimation has been applied to educational research, and, further, discusses some limitations of instrumental variables and issues that researchers should be cognizant of when employing instrumental variables.