Case-Deletion Measure Based on Q-Function for Exponential Family Nonlinear Mixed Models

Based on Q-function introduced by Zhu \& Lee (2001), this paper proposes some case-deletion measures for assessing the influence of an observation in exponential family nonlinear mixed models. The key idea is to treat the random effects as hypothetical missing data and works with the conditional expectation of the complete-data log-likelihood in the EM algorithm. An example illustrates our method.