Describes and assesses missing data methods currently used to analyze data from matrix sampling designs implemented by the National Assessment of Educational Progress. Several improved methods are developed, and these models are evaluated using an EM algorithm to obtain maximum likelihood estimates followed by multiple imputation of complete data…

With the view that social scientists conduct too little exploratory research, the author outlines the methods and attitudes of the exploratory analyst and describes the National Assessment of Educational Progress (NAEP) as a source of research data. Exploratory analysis, in which no paradigm is used, is contrasted with confirmatory research, which…