Can districts keep good teachers in the schools that need them most?

This study investigates how school demographics and their interactions with policies affect the mobility behaviors of public school teachers with various human capital characteristics. Using data from North Carolina from 1995 to 2006, it finds that teachers’ career stage and human capital investments dominate their decisions to leave public school teaching and school demographic characteristics play a dominant role in intra-system sorting. Schools serving at-risk children struggle to attract and retain teachers with desirable observable characteristics. We find evidence to suggest that across-the-board school-based pay-for-performance policies have small but significant associations with mobility decisions and appear to exacerbate inequities in the distribution of teacher qualifications.     

Anticipatory postural adjustments during cutting manoeuvres in football and their consequences for knee injury risk

Abstract

Anticipatory postural adjustments (APAs), i.e. preparatory positioning of the head, the trunk and the foot, are essential to initiate cutting manoeuvres during football games. The aim of the present study was to determine how APA strategies during cutting manoeuvres are influenced by a reduction of the time available to prepare the movement.

Thirteen football players performed different cutting tasks, with directions of cutting either known prior to the task or indicated by a light signal occurring 850, 600 or 500 ms before ground contact.

With less time available to prepare the cutting manoeuvre, the head was less orientated towards the cutting direction (P = 0.033) and the trunk was even more rotated in the opposite direction (P = 0.002), while the foot placement was not significantly influenced. Moreover, the induced higher lateral trunk flexion correlated with the increased knee abduction moment (r = 0.41; P = 0.009).

Increasing lateral trunk flexion is the main strategy used to successfully perform a cutting manoeuvre when less time is available to prepare the movement. However, higher lateral trunk flexion was associated with an increased knee abduction moment and therefore an increased knee injury risk. Reducing lateral trunk flexion during cutting manoeuvres should be part of training programs seeking the optimisation of APAs.     

The Issue of Range Restriction in Bookmark Standard Setting

This article uses data from a large‐scale assessment program to illustrate the potential issue of range restriction with the Bookmark method in the context of trying to set cut scores to closely align with a set of college and career readiness benchmarks. Analyses indicated that range restriction issues existed across different response probability (RP) values and item response theory (IRT) models if one were to apply the Bookmark procedure using intact test forms. Results also suggested that range restriction may still be present if one had access to additional data from an item bank. This demonstration critically highlights challenges that may exist in some practical applications of the Bookmark method due items not being designed to cover the full range of examinee abilities.     

Wherein Lies Children’s Intergroup Bias? Egocentrism,Social Understanding,and Social Projection

Does children’s bias toward their own groups reflect egocentrism or social understanding? After being categorized as belonging to 1 of 2 fictitious groups, 157 six‐ to ten‐year‐olds evaluated group members and expressed preferences among neutral items. Children who expected the in‐group to share their item preferences (egocentric social projection) showed intergroup bias. However, most bias was expressed by children who expected their in‐group to share, but the out‐group to oppose, their own evaluations of members. These oppositional expectations were associated with better social perspective taking, and better understanding that groups expect loyalty from their members. Consistent with the developmental model of subjective group dynamics (D. Abrams, A. Rutland, J. Pelletier, & J. M. Ferrell, 2009), social understanding, rather than egocentrism, provides a more parsimonious explanation of children’s intergroup bias.     

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