Cheng Yong Tang and Yongsong Qin
Biometrika (2012), pp. 1–7

We explore the use of estimating equations for efficient statistical inference in case of missing data. We propose a semi-parametric efficient empirical likelihood approach, and show that the empirical likelihood ratio statistic and its profile counterpart asymptotically follow central chi-square distributions when evaluated at the true parameter. The theoretical properties and practical performance of our approach are demonstrated through numerical simulations and data analysis.