When randomized experiments cannot be conducted in practice, propensity score (PS) techniques for matching treated and control units are frequently used for estimating causal treatment effects from observational data. Despite the popularity of PS techniques, they are not yet well studied for matching multilevel data where selection into treatment…

There is a degree of instability in any measurement, so that if it is repeated, it is possible that a different result may be obtained. Such instability, generally described as "measurement error", may affect the conclusions drawn from an investigation, and methods exist for allowing it. It is less widely known that different disciplines, and…

This study investigated the main effects of social support measures and their stress-buffering effects in two samples of homeless adults (Ns =249 and 219) obtained in the same large county (surrounding Detroit) at different points in time over an 8-year period (1992-1994 and 2000-2002). The findings suggest that the construct of social support,…

Survey research has played a major role in American social science. An outgrowth of efforts by the United States Department of Agriculture in the 1930s, the Division of Program Surveys (DPS) played an important role in the development of survey methodology. The DPS was headed by the ambitious and entrepreneurial Rensis Likert, populated by young…

Discussion of sampling methods used in information science research focuses on Fussler's method for sampling catalog cards and on sampling by length. Highlights include simple random sampling, sampling with probability equal to size without replacement, sampling with replacement, and examples of estimating the number of books on shelves in certain…

An investigation was conducted of the characteristics of two estimation procedures and corresponding test statistics used in the analysis of completely randomized factorial experiments when observations are lost at random. For one estimator, contrast coefficients for cell means did not involve the cell frequencies. For the other, contrast…

As an alternative to a classical test theory basis for criterion-referenced test construction, it is proposed that a strict item-sampling model be used. The computer's role in such a model is outlined. The assumptions of the model are carefully defined and its properties reviewed. The relationship between mastery criteria and such sampling plans…

Describes advances in capture-recapture modeling, including the biologically motivated emphasis on model-based hypothesis testing and the development of models for spatially stratified populations. Discusses the severe problems associated with count statistics reflecting unknown sampling fractions. (67 references) (KR)

Raw scores on most standardized educational and psychological assessment instruments acquire meaning only when referenced to a set of norms. Test publishers should clearly describe their norming procedures, including the target population and the sample on which the norms are based. The primary purpose of this report is to illustrate some of the…