Influence diagnostics in nonlinear reproductive dispersion models

We extend some diagnostic methods studied by Pregibon (1981, Arm. Statist. 9, 705-724), Cook and Weisberg (1982, Residuals and Influence in Regression, Chapman & Hall, New York), and Wei (1998, Exponential Family Nonlinear Models, Springer, Singapore) to nonlinear reproductive dispersion models (NRDM, Jorgensen, 1997, The Theory of Dispersion Models, Chapman & Hall, London). The equivalency of case-deletion models and mean-shift outlier models in NRDM is investigated. Some of the diagnostic measures are illustrated with an example. (C) 2000 Elsevier Science B.V. All rights reserved.