Research in learning progressions (LPs) has been essential towards building understanding of how students' ideas change over time. There has been little work, however, into how ideas between separate but related constructs within a multi-faceted LP relate. The purpose of this paper is to elaborate on the idea of "progression webs" to…

Discusses the application of path analysis in the context of genetic epidemiology. Examines the coherence of model specification, plausibility of modeling assumptions, the interpretability and usefulness of the model, and the validity of statistical procedures. (RB)