A Model of Rater Behavior in Essay Grading Based on Signal Detection Theory

An approach to essay grading based on signal detection theory (SDT) is presented. SDT offers a basis for understanding rater behavior with respect to the scoring of construct responses, in that it provides a theory of psychological processes underlying the raters' behavior. The approach also provides measures of the precision of the raters and the accuracy of classifications. An application of latent class SDT to essay grading is detailed, and similarities to and differences from item response theory (IRT) are noted. The validity and utility of classifications obtained from the SDT model and scores obtained from IRT models are compared. Validity coefficients were found to be about equal in magnitude across SDT and IRT models. Results from a simulation study of a 5-class SDT model with eight raters are also presented.     

Externalities, technological complementarities and sustained economic growth

Externalities as conventionally defined miss many of the spillovers that are both causes and consequences of the technological changes that underlie economic growth. We introduce a much wider concept called technological complementarities. New general purpose technologies (GPTs) rejuvenate the growth process by creating technological complementarities, which are adequately measured neither by total factor productivity (TFP) nor by externalities. There would be major gains from technological change even if the returns on capital invested in innovation never exceeded the returns on investing in existing technologies so that there were neither externalities nor positive changes in TFP.     

Identifying future scientists: predicting persistence into research training

This study used semistructured interviews and grounded theory to look for characteristics among college undergraduates that predicted persistence into Ph.D. and M.D./Ph.D. training. Participants in the summer undergraduate and postbaccalaureate research programs at the Mayo Clinic College of Medicine were interviewed at the start, near the end, and 8–12 months after their research experience. Of more than 200 themes considered, five characteristics predicted those students who went on to Ph.D. and M.D./Ph.D. training or to M.D. training intending to do research: 1) Curiosity to discover the unknown, 2) Enjoyment of problem solving, 3) A high level of independence, 4) The desire to help others indirectly through research, and 5) A flexible, minimally structured approach to the future. Web-based surveys with different students confirmed the high frequency of curiosity and/or problem solving as the primary reason students planned research careers. No evidence was found for differences among men, women, and minority and nonminority students. Although these results seem logical compared with successful scientists, their constancy, predictive capabilities, and sharp contrast to students who chose clinical medicine were striking. These results provide important insights into selection and motivation of potential biomedical scientists and the early experiences that will motivate them toward research careers.     

Teachers' education, classroom quality, and young children's academic skills: results from seven studies of preschool programs

In an effort to provide high-quality preschool education, policymakers are increasingly requiring public preschool teachers to have at least a Bachelor's degree, preferably in early childhood education. Seven major studies of early care and education were used to predict classroom quality and children's academic outcomes from the educational attainment and major of teachers of 4-year-olds. The findings indicate largely null or contradictory associations, indicating that policies focused solely on increasing teachers' education will not suffice for improving classroom quality or maximizing children's academic gains. Instead, raising the effectiveness of early childhood education likely will require a broad range of professional development activities and supports targeted toward teachers' interactions with children.     

Income is not enough: incorporating material hardship into models of income associations with parenting and child development

Although research has clearly established that low family income has negative impacts on children's cognitive skills and social-emotional competence, less often is a family's experience of material hardship considered. Using the Early Childhood Longitudinal Study, Kindergarten Class of 1998-1999 (N=21,255), this study examined dual components of family income and material hardship along with parent mediators of stress, positive parenting, and investment as predictors of 6-year-old children's cognitive skills and social-emotional competence. Support was found for a model that identified unique parent-mediated paths from income to cognitive skills and from income and material hardship to social-emotional competence. The findings have implications for future study of family income and child development and for identification of promising targets for policy intervention.     

Improving credibility assessment in child sexual abuse allegations: the role of the NICHD investigative interview protocol

OBJECTIVES: The study was designed to explore whether the credibility of children's statements regarding their alleged experiences of child sexual abuse could be assessed in a more valid and reliable way when investigative interviews were conducted using the NICHD protocol rather than in an unstructured manner. METHODS: Forty-two experienced Israeli youth investigators each assessed the credibility of allegations of sexual abuse made by alleged victims of sexual abuse when interviewed either with or without the protocol. Half of the alleged incidents were judged likely to have happened ("plausible") on the basis of independent evidence, while half were deemed unlikely to have happened ("implausible"). RESULTS: More non-protocol than protocol interviews were rated as "No judgment possible" rather than either credible or incredible. Allegations made in protocol interviews were more accurately rated as credible or incredible when they were either plausible or implausible, respectively, than those made in non-protocol statements. Levels of inter-rater reliability were also higher when protocol interviews were rated. The differences were significant only for plausible cases, however. CONCLUSIONS: The use of the NICHD protocol facilitated the assessment of credibility by child investigators although incredible allegations (those describing incidents that were unlikely to have happened) remained difficult to detect, even when the protocol was used.     

Developmental Precursors of Relational Aggression From Late Childhood Through Adolescence

Relational aggression—a psychological form of aggression—has numerous negative consequences for physical and emotional health. However, little is known about the risk factors that lead youth to engage in relational aggression. Using multimethod data from a longitudinal research of 674 Mexican-origin youth, this study examined the influence of parents, siblings, and peers on the development of relational aggression. Increases in relational aggression from age 10 to 16 were associated with: (a) low levels of parental monitoring and (b) increased association with deviant peers and siblings. These results held across gender and nativity status. The findings suggest that multiple socialization agents contribute to the development of relational aggression. We discuss the practical implications for reducing relational aggression during adolescence.