Simar and Wilson (J. Econometrics, 2007) provided a statistical model that can rationalize two-stage estimation of technical efficiency in non-parametric settings. Two-stage estimation has been widely used, but requires a strong assumption: the second-stage environmental variables cannot affect the support of the input and output variables in the first stage. In this paper, we provide a fully non-parametric test of this assumption; in addition, we provide a theoretical link to results obtained by Politis et al.(Statistica Sinica, 2001), allowing us to estimate critical values for our test statistics using bootstrap sub-sampling while optimizing the choice of sub-sample size by minimizing a measure of volatility. Our simulation results indicate that our tests perform well both in terms of size and power. We present a real-world empirical example by updating the analysis performed by Aly et al. (R. E. Stat., 1990) on U.S. commercial banks; our tests easily reject the assumption required for two-stage estimation, calling into question results that appear in hundreds of papers that have been published in recent years.
University of BolognaDipartimento di Scienze Aziendali
Clemson UniversityThe John E.Walker Department of Economics
Citations
APA
Chicago
FWB
Daraio, C., Simar, L., & Wilson, P. (2010). Testing whether two-stage estimation is meaningful in non-parametric models of production (ISBA Discussion Papers 1031). https://hdl.handle.net/2078.5/208718