The concept of Matthew effects in reading development refers to a longitudinally widening gap between high achievers and low achievers. Various statistical approaches have been proposed to examine this idea. However, little attention has been paid to psychometric issues of scaling. Specifically, interval-level data are required to compare…

There has been significant interest in examining the developmental factors that predispose individuals to chronic criminal offending. This body of research has identified some social-environmental risk factors as potentially important. At the same time, the research producing these results has generally failed to employ genetically sensitive…