Advanced Nonlinear Latent Variable Modeling: Distribution Analytic LMS and QML Estimators of Interaction and Quadratic Effects

Interaction and quadratic effects in latent variable models have to date only rarely been tested in practice. Traditional product indicator approaches need to create product indicators (e.g., x ₁ ², x ₁ x ₄) to serve as indicators of each nonlinear latent construct. These approaches require the use of complex nonlinear constraints and additional model specifications and do not directly address the nonnormal distribution of the product terms. In contrast, recently developed, easy-to-use distribution analytic approaches do not use product indicators, but rather directly model the nonlinear multivariate distribution of the measured indicators. This article outlines the theoretical properties of the distribution analytic Latent Moderated Structural Equations (LMS; Klein & Moosbrugger, 2000) and Quasi-Maximum Likelihood (QML; Klein & Muthén, 2007) estimators. It compares the properties of LMS and QML to those of the product indicator approaches. A small simulation study compares the two approaches and illustrates the advantages of the distribution analytic approaches as multicollinearity increases, particularly in complex models with multiple nonlinear terms. An empirical example from the field of work stress applies LMS and QML to a model with an interaction and 2 quadratic effects. Example syntax for the analyses with both approaches is provided.     

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Spillovers from publicly financed business R&D: some empirical evidence from Germany

This paper investigates the effects of interindustry R&D spillovers from publicly financed business R&D on private R&D efforts and productivity using data of West German manufacturing industries. The results suggest that it is important to distinguish between the effects of spillovers from privately and publicly financed business R&D. In particular, estimation results provide evidence of productivity-enhancing effects of spillovers from privately financed R&D while results are less clear-cut for publicly financed R&D. Moreover, there is some empirical evidence that private R&D efforts of higher-technology industries are stimulated by spillovers from privately financed R&D but not by spillovers from publicly financed R&D. However, public funding of R&D in higher-technology industries seems to induce private R&D investments within these industries.     

Ratings of usability of didactic models: a comparative case study in Croatia and Germany

The study refers to the unfavourable reputation and status of general didactics as well as its decreasing importance in teacher education. This is a result of poor performance achieved in international tests by students. They score low on knowledge and arguments, and empirical studies indicate that didactic models are useless. In view of the above problem, the aim of this article is to examine the validity of the argument that didactic models are useless. It is necessary to examine if general didactics are being in an unfavourable position along with its possible successors in the international context. In order to achieve that, we conducted an empirical study into the usability of didactic models for lesson planning in Croatia and compared it with the results obtained in previous research in Germany. The term usability means the advantages of theory in practice. On the basis of the results of the empirical study, we concluded that didactic models are not generally unusable. Additionally, they are different according to their usability. These results open a path for further research on this topic in the international context.     

A ménage à trois: the eye, the hand and on-line processing

This review summarizes research conducted in our laboratories over the past 5 years aimed at determining the temporal and spatial relationships between eye and hand movements and the amount of central processing that must occur before performing a manual aiming movement, relative to the amount of processing that is done online. All of our research to date points to a two-component model of speed-accuracy control in manual aiming. Several studies have shown that eye and hand movements in manual aiming are inextricably linked both temporally and spatially. Typically, the eye arrives in the vicinity of the target first; this coincides with peak acceleration of the finger during the initial impulse phase of a movement. There is also significant temporal and spatial coupling of the finger, elbow and shoulder in aiming, and movements appear to evolve in a proximal-to-distal fashion. Movements are endpoint driven and variability is reduced with distal approximation to the target. This movement control strategy means that visual information is not only available for use in modifying responses, but there is sufficient time available for its use. In sequential complex aiming movements, the use of visual feedback and on-line processing become even more important. Practice does not diminish the need for on-line processing; rather, its use appears to ensure greater movement efficiency.     

Embedded Clinical Librarianship: Bringing Medical Reference Services Bedside

This article was written by Patti Gibbons and Debra A. Werner. Patti is the Head of Collection Management at the University of Chicago Library’s Special Collections Research Center and holds a MLIS from the University of Illinois and a MA from the University of Washington. Debra is the Librarian for Science Instruction & Outreach and Biomedical Reference Librarian at the University of Chicago Library and the University of Chicago’s Pritzker School of Medicine’s Director of Library Research in Medical Education and she holds a MLIS from Dominican University. This article covers an experimental project at the University of Chicago where the library’s medical librarian teamed up with the hospital’s clinical team during patient rounds to provide real-time reference services. The project’s effectiveness was studied by a medical student who found that the embedded librarian’s services improved the clinical team’s evidence-based medical decision-making abilities without increasing the length of bedside rounds.     

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Activity profile of top-class association football referees in relation to performance in selected physical tests

The aims of the present study were (1) to analyse the physical demands of top-class referees and (2) to compare their official FIFA fitness test results with physical performance during a match. The work rate profiles of 11 international referees were assessed during 12 competitive matches at the 2003 FIFA Under-17 World Cup and then analysed using a bi-dimensional photogrammetric video analysis system based on direct lineal transformation (DLT) algorithms. In the first 15 min of matches, the referees were more active, performing more high-intensity exercise (P < 0.01) than in the first 15 min of the second half. During the second half of matches, the referees covered a shorter distance (P < 0.01), spent more time standing still (P < 0.05), and covered less ground cruising (P < 0.05), sprinting (P < 0.05), and moving backwards (P < 0.001) than in the first half. Also in the second 45 min, the distance of referees from infringements increased (P < 0.05) in the left attacking zone of the filed. There was also a decrease (P < 0.05) in performance in the period following the most high-intensity activity, compared with the mean for the 90 min. Time spent performing high-intensity activities during a match was not related to performance in the 12-min run (r(2) = 0.30; P < 0.05), the 200-m sprint (r(2) = 0.05; P < 0.05), or the 50-m sprint (r(2) = 0.001; P < 0.05). The results of this study show that: (1) top-class referees experienced fatigue at different stages of the match, and (2) the typical field tests used by FIFA (two 50-m and 200-m sprints, followed by a 12-min run) are not correlated with match activities.     

Characterizing mentoring capital in a residency program through mentor’s voices

The purpose of our study was to examine mentors’ conceptualizations of mentoring residents (preservice teachers) in a teacher residency program. Understanding the nuances of mentoring in a year-long placement in a mentor’s classroom may further illuminate mentoring in this context. In this qualitative, longitudinal study, we used constant comparative analysis to allow the data to drive recurring patterns and ideas linked to real-life situations and values coding to examine mentors’ conceptualizations of mentoring in a residency program. Residents enrolled in the federally-funded Teaching Residency Program for Critical Shortage Areas program were placed in a high-need urban secondary school for a year-long clinical experience to work alongside mentors, who had a non-evaluative role. By examining mentors’ conceptualizations of mentoring in this particular context, our data reveal aspects of their agency that reflected three main themes: (a) professional altruism, (b) extant knowledge, and (c) resident as stimulus. Our findings add to the research on mentoring by illuminating the voices of mentors to describe how they conceptualized mentoring and to further examine their motivations for mentoring, contributions to the mentee, and professional gains.