The effects of the Healthy Steps for Young Children Program: results from observations of parenting and child development

The Healthy Steps for Young Children Program (HS) is designed to provide support for new parents through the pediatrician's office. We present findings of the effect of HS on the quality of mother–child interaction, security of attachment, and child behavior using observational data from two of the HS sites that utilized a randomized treatment design. Results indicated that mothers participating in Healthy Steps were more likely to interact sensitively and appropriately than mothers in the comparison group at the second assessment point (age 34–37 months) but not at the first assessment point (age 16–18 months). There were no differences in child outcomes at either time point when the cross-sectional data were analyzed. However, the results of the longitudinal analysis (which included families who participated in the home observations at both Time 1 and Time 2) indicated that Healthy Steps participation was associated with greater security of attachment and fewer child behavior problems.     

Network representations of knowledge about chemical equilibrium: Variations with achievement

This study examined variation in the organization of domain-specific knowledge by 50 Year-12 chemistry students and 4 chemistry teachers. The study used nonmetric multidimensional scaling (MDS) and the Pathfinder network-generating algorithm to investigate individual and group differences in student concepts maps about chemical equilibrium. MDS was used to represent the individual maps in two-dimensional space, based on the presence or absence of paired propositional links. The resulting separation between maps reflected degree of hierarchical structure, but also reflected independent measures of student achievement. Pathfinder was then used to produce semantic networks from pooled data from high and low achievement groups using proximity matrices derived from the frequencies of paired concepts. The network constructed from maps of higher achievers (coherence measure = 0.18, linked pairs = 294, and number of subjects = 32) showed greater coherence, more concordance in specific paired links, more important specific conceptual relationships, and greater hierarchical organization than did the network constructed from maps of lower achievers (coherence measure = 0.12, linked pairs = 552, and number of subjects = 22). These differences are interpreted in terms of qualitative variation in knowledge organization by two groups of individuals with different levels of relative expertise (as reflected in achievement scores) concerning the topic of chemical equilibrium. The results suggest that the technique of transforming paired links in concept maps into proximity matrices for input to multivariate analyses provides a suitable methodology for comparing and documenting changes in the organization and structure of conceptual knowledge within and between individual students.     

Job Analysis for Lkensure and Certfication Exams: Science or Politics?

How might empirical j o b analysis give the appearance of science to a flawed public policy? How do “political” factors have an impact on the development of licensure tests? What are areas for future research and for improvement of prevailing practices in licensure and certification testingy?