Estimation of Time-Unstructured Nonlinear Mixed-Effects Mixture Models

Change over time often takes on a nonlinear form. Furthermore, change patterns can be characterized by heterogeneity due to unobserved subpopulations. Nonlinear mixed-effects mixture models provide one way of addressing both of these issues. This study attempts to extend these models to accommodate time-unstructured data. We develop methods to fit these models in both the structural equation modeling framework as well as the Bayesian framework and evaluate their performance. Simulations show that the success of these methods is driven by the separation between latent classes. When classes are well separated, a sample of 200 is sufficient. Otherwise, a sample of 1,000 or more is required before parameters can be accurately recovered. Ignoring individually varying measurement occasions can also lead to substantial bias, particularly in the random-effects parameters. Finally, we demonstrate the application of these techniques to a data set involving the development of reading ability in children.     

Successful development of generic capabilities in an undergraduate medical education program

The development of generic capabilities or graduate attributes in communication, teamwork, critical analysis of information, problem solving and ethical practice is widely recognised as a desired outcome of higher education. This emphasis on generic capabilities has emerged despite ongoing debates about the concept and development of such capabilities. A recent review of comprehensive audits of Australian universities has found little evidence that such outcomes are being achieved. We used data from four different evaluations, both qualitative and quantitative, to explore whether these important generic capabilities are being learned by undergraduate students in the University of New South Wales (UNSW) new Medicine Program. University of New South Wales medical students are significantly more positive than other UNSW students that their university experience is developing several generic capabilities. Measurements concerning generic skills development from the Australian 2009 Learning and Teaching Performance Fund process support these findings. Analyses of qualitative data from two methodologically different student surveys found consistent evidence that medical students value generic capability development in the UNSW program. Furthermore, we report evidence that current UNSW medical students rate their clinical learning in professional placements as a significantly better experience than students in the previous discipline-based program. We believe this is a consequence of generic capability learning in the early years of the new program, such that our students are better prepared to maximise the value of learning from professional experiences. Our results represent consistent evidence of successful generic capability development as a result of a program-wide innovation in undergraduate education. To validate further our conclusions, external assessments of our graduates' generic capabilities in-action in the workplace are currently being obtained.     

Selling home: Corporate stadium names and the destruction of commemoration

A city's primary benefits from professional sports franchises are civic pride and identification with its teams. The stadium or arena, as the physical “memory place”; for teams, has historically been named to commemorate the relationship among the team, the city, and the fans. This paper chronicles the rise in corporate naming and argues that sacrificing the commemorative name of a sports venue for a paid corporate name alters the identity statements of memory places, abbreviates the narrative about a city and its teams, and threatens the idyllic illusions about sports that fans have long chosen to maintain. As corporate naming spreads beyond sports, the substitution of commercialization for commemoration presents a growing threat to public memory places of many kinds.     

Creating greeting cards to understand and to evaluate Knapp’s Staircase Model of relationships

Courses: Interpersonal Communication, Relational Communication

Objective: This article teaches students to explain and evaluate Knapp’s Relational Staircase Model through the creation of personalized greeting cards for each relational stage. The in-class activity encourages students to be creative and succinct in capturing the essence of an assigned relational stage in their respective greeting cards. The activity also provides students with an opportunity to apply the model to their lives and to test the validity and usefulness of the model in the hook-up culture prevalent among many college students today.     

On the Correspondence between the Latent Growth Curve and Latent Change Score Models

There has been a great deal of work in the literature on the equivalence between the mixed-effects modeling and structural equation modeling (SEM) frameworks in specifying growth models (Willett &; Sayer, 1994). However, there has been little work on the correspondence between the latent growth curve model (LGM) and the latent change score model (see Grimm, Zhang, Hamagami, &; Mazzocco, 2013 Grimm, K. J., Zhang, Z., Hamagami, F., &; Mazzocco, M. M. (2013). Modeling nonlinear change via latent change and latent acceleration frameworks: Examining velocity and acceleration of growth trajectories. Multivariate Behavioral Research, 48, 117–143.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]). We demonstrate that four popular variants of the latent change score model – the no change, constant change, proportional change, and dual change models – have LGM equivalents. We provide equations that allow the translation of parameters from one approach to the other and vice versa. We then illustrate this equivalence using mathematics achievement data from the National Longitudinal Survey of Youth.     

Power of Two: The Impact of 2 Years of High Quality Teacher Child Interactions

The current study focuses on the cumulative effect on children’s early learning outcomes of the quality of teacher–child interactions over multiple years during early childhood. Using propensity score matching to minimize selection bias, we compared the academic outcomes of children who experienced consistently high-quality or consistently low-quality teacher–child interactions, as defined by the Classroom Assessment Scoring System, during prekindergarten and kindergarten. Research Findings: Results indicated statistically significant differences in directly assessed language and literacy skills between children who experienced consistently high- and consistently low-quality instructional support. This was true after just 1 year, and gains were even greater for children who experienced high levels of instructional support over 2 years. Emotional support and classroom organization were not associated with children’s academic learning. Practice or Policy: Although children experience cumulative benefits in response to high-quality instructional supports over 2 years, relatively few children have access to such opportunities. We discuss these results in light of limited consistency in children’s experiences over the early school years and the presence of selection bias.     

Topological realizability conditions and their interpretation for admittance matrices of an MTL system with mode delays

In a previous study by the authors regarding passive multiconductor transmission line (MTL) system quasi-TEM mode delay, we encounter longitudinal immittance matrix functions (LIMFs) whose behavior initially appears problematic, yet they are shown to be passive. This paper addresses the constraints on the realization of the admittance matrix and the physical interpretation of the realized circuits in the passive, common-ground microstrip system.