Researchers in psychology are increasingly using model selection strategies to decide among competing models, rather than evaluating the fit of a given model in isolation. However, such interest in model selection outpaces an awareness that one or a few cases can have disproportionate impact on the model ranking. Though case influence on the fit…

The current study proposes a new procedure for separately estimating slope change and level change between two adjacent phases in single-case designs. The procedure eliminates baseline trend from the whole data series before assessing treatment effectiveness. The steps necessary to obtain the estimates are presented in detail, explained, and…

This report summarizes research on experienced programmers' comprehension of computer programs that was carried out over a three-year contract period (1982-85). Following an extensive review of the programming skill literature, an analysis of programs based on the multiple abstractions (points-of-view) that characterize program text and design was…