Estimating Production Functions Using Inputs to Control for Unobservables
扩展了Olley和Pakes的方法，提出使用中间投入（而非投资）来控制不可观测的生产率冲击，从而解决投入与生产率之间的内生性问题，实证表明该方法效果显著。
We add to the methods for conditioning out serially correlated unobserved shocks to the production technology. We build on ideas first developed in Olley and Pakes (1996). They show how to use investment to control for correlation between input levels and the unobserved firm-specific productivity process. We show that intermediate inputs (those inputs which are typically subtracted out in a value-added production function) can also solve this simultaneity problem. We discuss some theoretical benefits of extending the proxy choice set in this direction and our empirical results suggest these benefits can be important. Copyright The Review of Economic Studies Limited, 2003.