Mixed- and Random-Effects Models

Data that are collected or generated in the context of any practical problem always exhibit variability. This variability calls for the use of appropriate statistical methodology for the data analysis. Data that are obtained from designed experiments are typically analyzed using a model that takes into consideration the various sources or factors that could account for the variability in the data. Here the term experiment denotes the process by which data are generated based on the basis of planned changes in one or more input variables that are expected to influence the response. The plan or layout used to carry out the experiment is referred to as an experimental design or design of the experiment. The analysis of the data is based on an appropriate ...