How can humans acquire relational representations that enable analogical inference and other forms of high-level reasoning? Using comparative relations as a model domain, we explore the possibility that bottom-up learning mechanisms applied to objects coded as feature vectors can yield representations of relations sufficient to solve analogy…

In multilevel modeling, group-level variables (L2) for assessing contextual effects are frequently generated by aggregating variables from a lower level (L1). A major problem of contextual analyses in the social sciences is that there is no error-free measurement of constructs. In the present article, 2 types of error occurring in multilevel data…

The use of cluster analysis, a multivariate classification technique, is advocated as a framework to guide the purposive selection of projects for multiple-case study research. A cluster analysis of a contrived data set demonstrates how the procedure is performed, and advantages and limitations are discussed. (SLD)

This paper shares the findings of an inquiry that evaluated 50 survey articles published in a refereed journal, "Educational Administration Quarterly," by examining the 53 sample designs reported in the articles. The paper presents a typology of the sample designs identified, discusses the problems of sample selection and estimation…

Statistically based risk assessment devices are widely used in criminal justice settings. Their promise remains largely unfulfilled, however, because assumptions and premises requisite to their development and application are routinely ignored and/or violated. This article provides a brief review of the most salient of these assumptions and…

Variation is a key concept in the study of statistics and its understanding is a crucial aspect of most statistically related tasks. This study aimed to extend and apply a hierarchy for describing students' understanding of variation that was developed in a sampling context to the context of a natural event in which variation occurs. Students aged…