Inferences on the mean of zero-inflated lognormal data: the generalized variable approach.

This paper considers the problems of confidence interval estimation and hypothesis testing for the mean of zero-inflated lognormal data. We present an unified novel approach based on the concepts of generalized test variables and generalized pivotal quantities. Simulation results demonstrate that the coverage accuracy of proposed confidence intervals and the type I error control of the proposed exact tests are satisfactory. 2005 John Wiley & Sons, Ltd.