Within evidence-based education, results from randomised controlled trials (RCTs), and meta-analyses of them, are taken as reliable evidence for effectiveness -- they speak to "what works". Extending RCT results requires establishing that study samples and settings are representative of the intended target. Although widely recognised as…

Selection bias is a problem for mathematics education researchers interested in using observational rather than experimental data to make causal inferences about the effects of different instructional methods in mathematics on student outcomes. Propensity score methods represent 1 approach to dealing with such selection bias. This article…

Two experiments examined the role of analogy in the development of a situation model of a target passage, specifically, whether an analogous source text could improve comprehension and inferencing about causal mechanisms in the target. Responses of analogy subjects were more likely to include given and inferred information that comprised the…

Two experiments investigated learning outcomes and comprehension processes when students learned about the heart and circulatory system using (a) text only, (b) text with simplified diagrams designed to highlight important structural relations, or (c) text with more detailed diagrams reflecting a more accurate representation. Experiment 1 found…