Higher Order Properties of GM and Generalized Empirical
Likelihood Estimators
Whitney Newey, Massachusetts Institute of Technology
Richard Smith, University of Bristol
Abstract
In an effort to improve the small sample properties of GMM, a number of
alternative estimators have been suggested. These include the empirical
likelihood (EL), continuous updating and exponential tilting estimators.
We show that these estimators share a common structure, being members of
a class of Generalized Empirical Likelihood (GEL) estimators. We use this
structure to compare their higher-order asymptotic properties. We find that
the asymptotic bias of EL often does not grow with the number of moment
restrictions, while that of GMM and other GEL estimators grows without
bound. We also use the formulae to derive bias corrected GMM and GEL
estimators. We find that bias corrected EL inherits the higher-order
property of maximum likelihood, that is asymptotically efficient relative
to the other bias corrected estimators.