This report is a study of statistical models and methods for analyzing nonstandard mixtures of distributions in auditing. It was prepared by the Committee on Applied and Theoretical Statistics of the Board on Mathematical Sciences, National Research Council, through its Panel on Nonstandard Mixtures of Distributions. A comprehensive survey of the various methodologies that have been provided in the literature is presented, together with numerical examples. A detailed annotated bibliography of statistical practice in auditing is included.

The general objectives of this report are to provide a summary of the state-of-the-art in discriminant analysis and clustering and to identify key research and unsolved problems that need to be addressed in these two areas. It was prepared under the auspices of the Committee on Applied and Theoretical Statistics of the Board on Mathematical Sciences, National Research Council by its Panel on Discriminant Analysis, Classification, and Clustering. Both methodological and theoretical aspects are reviewed, and a survey of available software and algorithms is provided.