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1.
Children are capable of viewing object ownership as categorical and exclusive, but ownership claims can also vary by degree. This study investigated how children use these different conceptions of ownership in a giving and a taking task. In two studies, 4- to 7-year olds (= 105) could give and take craft objects that they or another child had found (weaker claim) and made (stronger claim). In Study 1, no additional ownership information was given, and in Study 2 categorical ownership was stated (“these belong to you”). The results showed that children used categorical ownership for their own objects but used ownership strength for the other child's objects, taking more of the found items.  相似文献   
2.
Evidence of the internal consistency of standard-setting judgments is a critical part of the validity argument for tests used to make classification decisions. The bookmark standard-setting procedure is a popular approach to establishing performance standards, but there is relatively little research that reflects on the internal consistency of the resulting judgments. This article presents the results of an experiment in which content experts were randomly assigned to one of two response probability conditions: .67 and .80. If the standard-setting judgments collected with the bookmark procedure are internally consistent, both conditions should produce highly similar cut scores. The results showed substantially different cut scores for the two conditions; this calls into question whether content experts can produce the type of internally consistent judgments that are required using the bookmark procedure.  相似文献   
3.
ABSTRACT

To maintain the accuracy of squash shots under varying conditions, such as the oncoming ball’s velocity and trajectory, players must adjust their technique. Although differences in technique between skilled and less-skilled players have been studied, it is not yet understood how players vary their technique in a functional manner to maintain accuracy under varying conditions. This study compared 3-dimensional joint and racket kinematics and their variability between accurate and inaccurate squash forehand drives of 9 highly skilled and 9 less-skilled male athletes. During inaccurate shots, less-skilled players hit the ball with a more open racket, demonstrating a difference in this task-relevant parameter. No joint kinematic differences were found for accuracy for either group. Coordinated joint rotations at the elbow and wrist both displayed a “zeroing-in” effect, whereby movement variability was reduced from the initiation of propulsive joint rotation to a higher consistency at ball-impact; potentially highlighting the “functionality” of the variability prior to the impact that enabled consistent task-relevant parameters (racket orientation and velocity) under varying conditions. Further, highly skilled players demonstrated greater consistency of task-relevant parameters at impact than less-skilled players. These findings highlight the superior ability of highly skilled players to adjust their technique to achieve consistent task-relevant parameters and a successful shot.  相似文献   
4.
Reading and Writing - Reading and writing are distinct skill areas that influence each other across development. Children with autism spectrum disorder (ASD) are noted to exhibit challenges in both...  相似文献   
5.
Magnetic-inertial measurement units (MIMUs) are becoming more prevalent in sports biomechanics and may be a viable tool to evaluate kinematic parameters. This study examined the accuracy of a MIMU to estimate orientation angles under static conditions and dynamically from a squash racket during a forehand drive shot. A MIMU was mounted onto a goniometer and moved through 0–90°, with static data collected at 10° increments during 10 repetitions of all three axes. Typical error analyses showed the MIMU to be very reliable (TE ≤ 0.03°). MIMU accuracy was determined via intraclass correlation coefficients (ICC) (r > 0.999, p < 0.001). An ordinary least products regression showed no proportional bias and minimal fixed bias for all axes. Dynamic accuracy was assessed by comparing MIMU and optical motion capture data of squash racket swing kinematics. A MIMU was fixed onto a racket and 10 participants each hit 10 forehand shots. Mean orientation angle error at ball impact was <0.50° and ICC showed very high correlations (r ≥ 0.988, p < 0.001) for all orientations. Swing phase root mean squared errors were ≤2.20°. These results indicate that a MIMU could be used to accurately and reliably estimate selected racket swing kinematics.  相似文献   
6.
This study examined differential and mediating relations between hot and cool self-regulation (Mage = 48.2 months; = 1,155, 48% girls), first-grade (Mage = 77.5 months) maladjustment (externalizing [EXT] and internalizing [INT] behavior), and first- and second-grade (Mage = 89.5 months) academic competence (AC). Using teacher reported EXT, INT, and AC, partial support for the differential perspective was found in that only hot self-regulation was significantly related to EXT, whereas both hot and cool self-regulation was significantly related to AC. Moreover, hot self-regulation indirectly predicted second-grade AC through first-grade EXT, lending some support for the mediating perspective also. The findings contribute to an understanding of how self-regulation is related to academic and behavioral school adjustment.  相似文献   
7.
ABSTRACT

Teachers’ professional knowledge is considered one of the most important predictors of instructional quality. According to Shulman, such professional knowledge includes content, pedagogical content and pedagogical knowledge. Although recent research shed some light on the structure of the dimensions of professional knowledge, little is known how teacher education impacts pre-service physics teachers’ professional knowledge. In an effort to address this issue, we examined the content, pedagogical content and pedagogical knowledge of N?=?200 pre-service physics teachers enrolled in different years of teacher education at 12 major teacher education universities in Germany. We used structural equation modelling (1) to examine the relations amongst pre-service physics teachers’ content, pedagogical content and pedagogical knowledge, (2) to explore how the three kinds of knowledge and their relations differ across different stages of teacher education and (3) to identify factors affecting the level of each component of professional knowledge. Our findings suggest that content, pedagogical content and pedagogical knowledge represent distinct types of knowledge. Furthermore, our findings show that in the first years of professional education, pedagogical content knowledge is more closely related with general pedagogical knowledge while in later years, it is more closely related with content knowledge, suggesting that it develops from a general knowledge about teaching and learning into knowledge about the teaching and learning of specific content. Finally, beyond school achievement and years of enrolment as predictors, we find in particular the amount of classroom observations to have a positive impact on the professional knowledge of pre-service physics teachers.  相似文献   
8.
9.
Assessing comfort of running footwear reliably is challenging. The purpose of this study was to compare the intra-rater reliability between different assessment types, to calculate intra-individual reliability scores and to evaluate the effect of rater selection based on individual reliability scores on group level reliability. Three assessment types: ranking, Visual Analogue Scale (VAS), and Likert Scale (LS) were provided twice in six separate sessions among 30 participants, who assessed comfort of five shoes after treadmill running. Spearman's rho provided an evaluation of inter-session relative reliability and typical error as a measure of absolute reliability for each assessment type. Ranking (r?=?0.70, 95% confidence interval [CI] 0.61–0.78) yielded the highest relative reliability for overall comfort, followed by VAS (r?=?0.67, 95% CI 0.56–0.75) and LS (r?=?0.63, 95% CI 0.52–0.72), with large-scale overlaps of CIs between assessment types. The same order of assessment types was found for the percentage of reliable raters (r?≥?0.7) with 60% in ranking scale, 47% in VAS and 37% in LS. Forming subgroups corresponding to the intra-individual reliability substantially increased group level reliabilities. Based on measures of relative reliability, an extreme reduction in resolution as provided by the ranking from pairwise comparisons seems to be a valuable tool in footwear comfort assessments if assessment time is of minor importance. No preference can be provided for the two investigated rating scales. Besides the assessment type, a selection of the best raters in additional reliability checks seems to be a prerequisite for further comfort-related studies.  相似文献   
10.
This investigation assessed the effect of dietary nitrate (NO3?) supplementation, in the form of beetroot juice (BR), on repeat-sprint performance in normoxia and normobaric hypoxia. 12 male team-sport athletes (age 22.3 ± 2.6 y, VO2peak 53.1 ± 8.7 mL.kg?1.min?1) completed three exercise trials involving a 10 min submaximal warm-up and 4 sets of cycling repeat-sprint efforts (RSE; 9 × 4 s) at sea level (CON), or at 3000 m simulated altitude following acute supplementation (140 mL) with BR (HYPBR; 13 mmol NO3?) or NO3depleted BR placebo (HYPPLA). Peak (PPO) and mean (MPO) power output, plus work decrement were recorded during the RSE task, while oxygen consumption (VO2) was measured during the warm-up. There were no significant differences observed between HYPBR and HYPPLA for PPO or MPO; however, work decrement was reduced in the first RSE set in HYPBR compared with HYPPLA. There was a moderate effect for VO2 to be lower following BR at the end of the 10 min warm-up (ES = 0.50 ± 0.51). Dietary NO3? may not improve repeat-sprint performance in hypoxia but may reduce VO2 during submaximal exercise. Therefore, BR supplementation may be more effective for performance improvement during predominantly aerobic exercise.  相似文献   
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