Tests of additivity in mixed and fixed effect two-way ANOVA models with single sub-class numbers

In variety testing as well as in psychological assessment, the situation occurs that in a two-way ANOVA-type model with only one replication per cell, analysis is done under the assumption of no interaction between the two factors. Tests for this situation are known only for fixed factors and normally distributed outcomes. In the following we will present five additivity tests and apply them to fixed and mixed models and to quantitative as well as to Bernoulli distributed data. We consider their performance via simulation studies with respect to the type-I-risk and power. Furthermore, two new approaches will be presented, one being a modification of Tukey's test and the other being a new experimental design to test for interactions

Validity of the developmental test of visual-motor integration supplemental developmental test of visual perception

It is well known that skilled batters in fast-ball sports do not align their gaze with the ball throughout ball-flight, but instead adopt a unique sequence of eye and head movements that contribute toward their skill. However, much of what we know about visual-motor behavior in hitting is based on studies that have employed case study designs, and/or used simplified tasks that fall short of replicating the spatiotemporal demands experienced in the natural environment. The aim of this study was to provide a comprehensive examination of the eye and head movement strategies that underpin the development of visual-motor expertise when intercepting a fast-moving target. Eye and head movements were examined in situ for 4 groups of cricket batters, who were crossed for playing level (elite or club) and age (U19 or adult), when hitting balls that followed either straight or curving ('swinging') trajectories. The results provide support for some widely cited markers of expertise in batting, while questioning the legitimacy of others. Swinging trajectories alter the visual-motor behavior of all batters, though in large part because of the uncertainty generated by the possibility of a variation in trajectory rather than any actual change in trajectory per se. Moreover, curving trajectories influence visual-motor behavior in a nonlinear fashion, with targets that curve away from the observer influencing behavior more than those that curve inward. The findings provide a more comprehensive understanding of the development of visual-motor expertise in interception. (PsycINFO Database Recor

An evaluation of the validity of the Test of Visual Perceptual Skills - Revised (TVPS-R) using the Rasch Measurement Model

The visual perceptual skills of children are often evaluated by health care and education practitioners. Even though the Test of Visual Perceptual Skills - Revised (TVPS-R) is one of the most frequently used instruments with school-age children, its construct validity has not been evaluated thoroughly. The purpose of the study was to evaluate the scalability/interval level measurement, unidimensionality, lack of differential item functioning (DIF), and hierarchical ordering of items of the TVPS-R and its seven subscales using the Rasch Measurement Model (RMM). The TVPS-R scores from a sample of 356 normally developing children (171 boys and 185 girls), ranging in age from 5 to 11 years, were used to complete the RMM analysis. When the seven individual TVPS-R scales were analysed, they all exhibited adequate measurement properties (scalability/interval level measurement, unidimensionality, lack of DIF, and hierarchical ordering). However, when they were collapsed together to form an overall composite scale of motor-free visual perceptual skills, the TVPS-R items failed to group together to measure a unidimensional construct. In addition, many scale items exhibited RMM misfit or DIF. The results suggest that the seven TVPS-R subscales can be used on an individual basis with clients to generate a profile of their motor-free visual perceptual skills, but that they cannot be summed together to calculate an overall summary motor-free visual perceptual score or perceptual quotient. The TVPS-R composite scale does not exhibit adequate construct validity