A Unified Latent Growth Curve Model

Applying item response theory models to repeated observations has demonstrated great promise in developmental research. By allowing the researcher to take account of the characteristics of both item response and measurement error in longitudinal trajectory analysis, it improves the reliability and validity of latent growth curve analysis. This has enabled the study, to differentially weigh individual items and examine developmental stability and change over time, to propose a comprehensive modeling framework, combining a measurement model with a structural model. Despite a large number of components requiring attention, this study focuses on model formulation, evaluates the performance of the estimators of model parameters, incorporates prior knowledge from Bayesian analysis, and applies the model using an illustrative example. It is hoped that this fundamental study can demonstrate the breadth of this unified latent growth curve model.     

It’s not the economy, stupid! External effects on the supply and demand of cinema entertainment

The paper addresses whether the state of the economy impacts the supply of and demand for cinema entertainment. A literature review on the drivers of cinema supply and demand is provided, and two competing hypotheses are extracted. Economic downturns could either lead to a sober mood and drive the interest in serious genres or drive the need for distraction leading to an increased interest in feel-good or action movies. However, characteristics of the movie industry suggest that economic key factors have only limited effects on supply and demand. A time series analysis of supply and demand in three major European markets indicate that demand is unrelated to the state of the economy. In aggregate, the demand does not instruct supply. Fluctuations in individual movie quality superpose potential effects of the economic context on the aggregated demand. Simultaneously, a focus on film as art superposes potential effects of the economic context on the supply.     

Spike jump biomechanics in male versus female elite volleyball players

ABSTRACT

There are well-known biological differences between women and men, especially in technical-coordinative variations that contribute to sex differences in performance of complex movements like the most important offensive action in volleyball, the spike jump. The aim of this study was to investigate sex-dependent performance and biomechanical characteristics in the volleyball spike jump. Thirty female and male sub-elite volleyball players were analysed while striking a stationary ball with maximal spike jump height. Twelve MX13 Vicon cameras with a cluster marker set, two AMTI force plates, surface EMG, and a Full-Body 3D model in Visual3D were used. Main findings include sex differences (P< .05) in jump height (pη² = .73), approach [speed (pη² = .61), step length], transition strategy [plant angle, neuromuscular activation (pη² = .91), horizontal force maxima and impulses], acceleration distances [centre of mass displacement (pη² = .21), minimal knee and hip angles], use of torso and arms [incline, angular velocity (pη² = .23)]. Correlations support that the results cannot be explained fully by strength and power differences between sexes but represent the product of technical-coordinative variations. Their relevance is acknowledged for both sexes and numerous performance determinants displayed sex differences. The integration of such attributes into sex-specific training seems promising but its effect requires further investigation.     

Local Equating Using the Rasch Model,the OPLM,and the 2PL IRT Model—or—What Is It Anyway if the Model Captures Everything There Is to Know About the Test Takers?

Local equating (LE) is based on Lord's criterion of equity. It defines a family of true transformations that aim at the ideal of equitable equating. van der Linden (this issue) offers a detailed discussion of common issues in observed‐score equating relative to this local approach. By assuming an underlying item response theory model, one of the main features of LE is that it adjusts the equated raw scores using conditional distributions of raw scores given an estimate of the ability of interest. In this article, we argue that this feature disappears when using a Rasch model for the estimation of the true transformation, while the one‐parameter logistic model and the two‐parameter logistic model do provide a local adjustment of the equated score.     

NASTY,BRUTISH AND LONG: ADVENTURES IN OLD AGE AND THE WORLD OF ELDERCARE By Ira Rosofsky

Nurses play a significant role in geriatric care. However, as the aging population and demand for geriatric nurses increase worldwide, shortages of nurses seem to arise. This creates the need to assess and address the motivation and attitudes of nurses toward geriatric care. The intent of this qualitative study is to surface the essence or the “lebenswelt” that describe the motivation and attitudes of a selected group of Filipino nurses toward geriatric care. A total of six registered nurses who had experienced taking care of elderly patients voluntarily participated as respondents of this study. A two-part instrument developed by the researchers was made to elicit necessary data and information. The first part comprised of the robotfoto intended to establish the baseline characteristics of nurses under study. The second part consisted of a semistructured individual in-depth interview using “aide memoire” to probe into the motivation and attitudes of the nurse respondents. Field texts were phenomenologically reduced via repertory grid. Two distinct and interesting themes, namely Geriatric Service Motivation Typology and the Yin-Yang of Geriatric Attitudes emerged. The first theme includes the Single Loop and Double Loop type of motivation The former involves a transactional and unidirectional process, while the latter constitutes a two-way relational and transformational process. The second theme consists of a harmonious combination of the two sides of the nurses' attitudes toward geriatric care. Through this study, the human side of nursing is seen and captured, thus increasing the awareness and knowledge of nurses, improving provision of optimum geriatric care, and inspiring nurses to pursue geriatric nursing with a yearning to serve the elderly with and from the heart.     

Resilience Among Children Exposed to Domestic Violence: The Role of Risk and Protective Factors

Individual and family characteristics that predict resilience among children exposed to domestic violence (DV) were examined. Mother–child dyads ( n  =   190) were assessed when the children were 2, 3, and 4 years of age. DV-exposed children were 3.7 times more likely than nonexposed children to develop internalizing or externalizing problems. However, 54% of DV-exposed children maintained positive adaptation and were characterized by easy temperament (odds ratio [OR] = .39, d  = .52) and nondepressed mothers (OR = 1.14, d  = .07), as compared to their nonresilient counterparts. Chronic DV was associated with maternal depression, difficult child temperament, and internalizing or externalizing symptoms. Results underscore heterogeneous outcomes among DV-exposed children and the influence of individual and family characteristics on children's adaptation.     

Many-Level Multilevel Structural Equation Modeling: An Efficient Evaluation Strategy

Structural equation models are increasingly used for clustered or multilevel data in cases where mixed regression is too inflexible. However, when there are many levels of nesting, these models can become difficult to estimate. We introduce a novel evaluation strategy, Rampart, that applies an orthogonal rotation to the parts of a model that conform to commonly met requirements. This rotation dramatically simplifies fit evaluation in a way that becomes more potent as the size of the data set increases. We validate and evaluate the implementation using a 3-level latent regression simulation study. Then we analyze data from a statewide child behavioral health measure administered by the Oklahoma Department of Human Services. We demonstrate the efficiency of Rampart compared to other similar software using a latent factor model with a 5-level decomposition of latent variance. Rampart is implemented in OpenMx, a free and open source software package.     

A bottlenose dolphin discriminates visual stimuli differing in numerosity

A bottlenose dolphin was trained to discriminate two simultaneously presented stimuli differing in numerosity (defined by the number of constituent elements). After responding correctly to stimuli consisting of three-dimensional objects, the dolphin transferred to two-dimensional stimuli. Initially, a variety of stimulus parameters covaried with the numerosity feature. By systematically controlling for these stimulus parameters, it was demonstrated that some of these attributes, such as element configuration and overall brightness, affected the animal’s discrimination performance. However, after all the confounding parameters were under control, the dolphin was able to discriminate the stimuli exclusively on the basis of the numerosity feature. The animal then achieved a successful transfer to novel numerosities, both intervening numerosities and numerosities outside the former range. These findings provide substantial evidence that the dolphin could base his behavior on the numerosity of a set independently of its other attributes and that he represented ordinal relations among numerosities.