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591.
Studies investigating invariance have often been limited to measurement or prediction invariance. Selection invariance, wherein the use of test scores for classification results in equivalent classification accuracy between groups, has received comparatively little attention in the psychometric literature. Previous research suggests that some form of selection bias (lack of selection invariance) will exist in most testing contexts, where classification decisions are made, even when meeting the conditions of measurement invariance. We define this conflict between measurement and selection invariance as the invariance paradox. Previous research has found test reliability to be an important factor in minimizing selection bias. This study demonstrates that the location of maximum test information may be a more important factor than overall test reliability in minimizing decision errors between groups. 相似文献
592.
Michael J. Duncan Alexandra P. Dobell Chloe L. Caygill Emma Eyre Jason Tallis 《European Journal of Sport Science》2019,19(1):103-111
AbstractThe current study examined the effect of acute caffeine ingestion on mean and peak power production during upper body Wingate test (WANT) performance, rating of perceived exertion, readiness to invest effort and cognitive performance. Using a double-blind design, 12 males undertook upper body WANTs, following ingestion of caffeine (5?mg*kg?1) or placebo. Pre-substance ingestion, 60?mins post substance ingestion and post exercise participants completed measures of readiness to invest physical and mental effort and cognitive performance. Peak power was significantly higher (P?=?.026), fatigue index greater (P?=?.02) and rating of perceived exertion lower (P?=?.025) in the presence of caffeine. Readiness to invest physical effort was also higher (P?=?.016) in the caffeine condition irrespective of time point (pre, 60?mins post ingestion and post exercise). Response accuracy for incongruent trials on the Flanker task was superior in the presence of caffeine (P?=?.006). There was a significant substance?×?time interaction for response speed in both congruent and incongruent conditions (both P?=?.001) whereby response speeds were faster at 60?mins post ingestion and post exercise in the caffeine condition, compared to placebo. This is the first study to examine the effects of caffeine ingestion on this modality of exercise and suggests that caffeine ingestion significantly enhances peak power, readiness to invest physical effort, and cognitive performance during WANT performance. 相似文献
593.
The current study examined study habits of postsecondary students with attention-deficit/hyperactivity disorder (ADHD) through the theoretical context of deliberate practice. The responses of participants with and without ADHD were compared on a survey of study time, study quality, and self-perceptions of study habits, as well as a measure of test anxiety. Groups were equivalent on reports of study time and time spent in other activities, percentage of classes they attend, use of conducive study environments, and planning of studying. Despite similar study behaviors, ADHD participants were more likely to feel unprepared for tests, reported significantly higher test anxiety, and had lower grade point averages. Regardless of ADHD status, the majority of study participants were not implementing deliberate practice behaviors, with the exception of class attendance, and study times fell far below recommended levels. Findings provided evidence that emulating the study behaviors of peers is not sufficient for students with ADHD to experience similar outcomes. 相似文献
594.
This study examines the prevalence of home–school match in childrearing beliefs and socialization practices (control and support) and their relation to ethnicity and readiness skills of children (n = 310) making the transition from publicly sponsored Pre-k to kindergarten. Home–school match was operationalized both as a continuous absolute measure and as categories of match or mismatch. Overall, home–school match was more prevalent than mismatch. However, the results corroborate previous ethnographic studies showing higher rates of home–school mismatch among African Americans and Latinos than Euro Americans. Controlling for race and socio-economic status, parents’ beliefs and practices predicted readiness but teachers’ did not. Absolute indicators of home–school differences were not related to kindergarten readiness. Directional indicators revealed that children attained greater skills when parents and teachers matched on child-centered beliefs, low control, and high support. Contrary to the cultural match hypothesis, home–school mismatch was associated with better outcomes than match in the case of adult-centered beliefs, control, and low support. 相似文献
595.
Rochelle E. Tractenberg Jason G. Umans Robert J. McCarter 《Assessment & Evaluation in Higher Education》2010,35(1):15-32
This article describes a ‘Mastery Rubric’ (MR) used to design both the curriculum and the assessments in a new two‐year certificate programme intended to train physicians in clinical research skills. The MR for clinical research skills is built around a set of core research skills: critical review of literature; articulation of research objective; development of research design; development of analysis plan; implementation of the study; implementation of the analysis plan and presentation of results. Four distinct levels of performance are described for each skill: beginning, novice, competent and proficient. This rubric outlines and provides a path to mastery of the clinical research skills the certificate programme was designed and funded to target. Using the rubric to design the curriculum ensures that courses will provide instruction in key domains, promotes assessment that demonstrates development in the target skills and knowledge, and encourages reflection and cognitive self‐monitoring in the students. It is a flexible, criterion‐referenced definition of ‘success’ for students as well as the programme itself. The criteria are characterised in terms of the skills, habits of mind and organisational principles that can foster excellence in clinical research, but the approach can be generalised. 相似文献
596.
We investigated: (a) the associations of implicit theories and epistemological beliefs and their effects on the academic motivation and achievement of students in Grade 6 science and (b) the mean differences of implicit theories, epistemological beliefs, and academic motivation and achievement as a function of gender and race/ethnicity (N = 508). Path analysis revealed that an incremental view of ability had direct and indirect effects on adaptive motivational factors, whereas fixed entity views had direct and indirect effects on maladaptive factors. Epistemological beliefs mediated the influence of implicit theories of ability on achievement goal orientations, self-efficacy, and science achievement. Results are discussed in relation to Dweck and Leggett’s (1988) social-cognitive theory with a focus on middle school science. 相似文献
597.
JD Vescovi 《Journal of sports sciences》2012,30(12):1259-1265
Abstract The aim of this study was to determine sprint profiles of professional female soccer players and evaluate how various speed thresholds impact those outcomes. Seventy-one professional players competing in full matches were assessed repeatedly during 12 regular season matches using a Global Positioning System (GPS). Locomotion ≥18?km?·?h(-1) was defined as sprinting and each event was classified into: Zone 1: 18.0-20.9?km· h(-1); Zone 2: 21.0-22.9?km?·?h(-1); Zone 3: 23.0-24.9?km?·?h(-1) and Zone 4: >25?km?·?h(-1). Outcomes included: duration (s), distance (m), maximum speed (km?·?h(-1)), duration since previous sprint (min) and proportion of total sprint distance. In total 5,019 events were analysed from 139 player-matches. Mean sprint duration, distance, maximum speed and time between sprints were 2.3?±?1.5?s, 15.1?±?9.4?m, 21.8?±?2.3?km· h(-1), and 2.5?±?2.5?min, respectively. Mean sprint distances were 657?±?157, 447?±?185, and 545?±?217?m for forwards, midfielders and defenders, respectively (P?≤?0.046). Midfielders had shorter sprint duration (P = 0.023), distance (P?≤?0.003) and maximum speed (P?0.001), whereas forwards performed more sprints per match (43?±?10) than midfielders (31?±?11) and defenders (36?±?12) (P?≤?0.016). Forty-five percent, 29%, 15%, and 11% of sprints occurred in sprint Zones 1, 2, 3 and 4, respectively. This group of professional female soccer players covered 5.3?±?2.0% of total distance ≥18?km?·?h(-1) with positional differences and percent decrements distinct from other previously identified elite players. These data should guide the development of high intensity and sprint thresholds for elite-standard female soccer players. 相似文献
598.
Automatic tracing and segmentation of rat mammary fat pads in MRI image sequences based on cartoon-texture model 总被引:1,自引:1,他引:0
The growth patterns of mammary fat pads and glandular tissues inside the fat pads may be related with the risk factors of breast cancer.Quantitative measurements of this relationship are available after segmentation of mammary pads and glandular tissues.Rat fat pads may lose continuity along image sequences or adjoin similar intensity areas like epidermis and subcutaneous regions.A new approach for automatic tracing and segmentation of fat pads in magnetic resonance imaging (MRI) image sequences is presented,which does not require that the number of pads be constant or the spatial location of pads be adjacent among image slices.First,each image is decomposed into cartoon image and texture image based on cartoon-texture model.They will be used as smooth image and feature image for segmentation and for targeting pad seeds,respectively.Then,two-phase direct energy segmentation based on Chan-Vese active contour model is applied to partitioning the cartoon image into a set of regions,from which the pad boundary is traced iteratively from the pad seed.A tracing algorithm based on scanning order is proposed to accurately trace the pad boundary,which effectively removes the epidermis attached to the pad without any post processing as well as solves the problem of over-segmentation of some small holes inside the pad.The experimental results demonstrate the utility of this approach in accurate delineation of various numbers of mammary pads from several sets of MRI images. 相似文献
599.
Paul C. Quinn Matthew M. Doran Jason E. Reiss and James E. Hoffman 《Child development》2009,80(1):151-161
Previous looking time studies have shown that infants use the heads of cat and dog images to form category representations for these animal classes. The present research used an eye-tracking procedure to determine the time course of attention to the head and whether it reflects a preexisting bias or online learning. Six- to 7-month-olds were familiarized with cats or dogs in upright or inverted orientations and then tested with a novel cat and novel dog in the same orientation. In the upright orientation, infants fixated head over body throughout familiarization; with inversion, no head preference was observed. These findings suggest that infant reliance on the head to categorize cats versus dogs results from a bias that pushes attention to the head. 相似文献
600.