Chen, Xiaohong; Hahn, Jinyong; Liao, Zhipeng - Centre for Microdata Methods and Practice (CEMMAP) - 2012
In this note, we characterise the semiparametric efficiency bound for a class of semiparametric models in which the unknown nuisance functions are identified via nonparametric conditional moment restrictions with possibly non-nested or over-lapping conditioning sets, and the finite dimensional...