Paper presented at the fall 2007 Association for Public Policy Analysis and Management conference held in Washington, DC.

This paper examines both theoretically and empirically whether using ordinary least squares (OLS) multivariate regression models to estimate average treatment effects under experimental designs is justified by the Neyman model for causal inference. The paper finds that estimated standard errors...

Paper presented at the fall 2007 Association for Public Policy Analysis and Management conference held in Washington, DC.