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751.
Marja van den Heuvel-Panhuizen Alexander Robitzsch Adri Treffers Olaf Köller 《Psychometrika》2009,74(2):351-365
This article discusses large-scale assessment of change in student achievement and takes the study by Hickendorff, Heiser,
Van Putten, and Verhelst (2009) as an example. This study compared the achievement of students in the Netherlands in 1997 and 2004 on written division problems.
Based on this comparison, they claim that there is a performance decline in this subdomain of mathematics, and that there
is a move from applying the digit-based long division algorithm to a less accurate way of working without writing down anything.
In our discussion of this study, we address methodological challenges that come in when investigating long-term trends in
student achievements, such as the need for adequate operationalizations, the influence of the time of measurement and the
necessity of the comparability of assessments, the effect of the assessment format, and the importance of inclusion relevant
covariates in item response models. All these issues matter when assessing change in student achievement. 相似文献
752.
Response times on test items are easily collected in modern computerized testing. When collecting both (binary) responses
and (continuous) response times on test items, it is possible to measure the accuracy and speed of test takers. To study the
relationships between these two constructs, the model is extended with a multivariate multilevel regression structure which
allows the incorporation of covariates to explain the variance in speed and accuracy between individuals and groups of test
takers. A Bayesian approach with Markov chain Monte Carlo (MCMC) computation enables straightforward estimation of all model
parameters. Model-specific implementations of a Bayes factor (BF) and deviance information criterium (DIC) for model selection
are proposed which are easily calculated as byproducts of the MCMC computation. Both results from simulation studies and real-data
examples are given to illustrate several novel analyses possible with this modeling framework.
The authors thank Steven Wise, James Madison University, and Pere Joan Ferrando, Universitat Rovira i Virgili, for generously
making available their data sets for the empirical examples in this paper. 相似文献
753.
van Loosbroek E Dirkx GS Hulstijn W Janssen F 《Journal of experimental child psychology》2009,102(1):26-39
Our study focused on number transcoding in children. It investigated how 9-year-olds with and without arithmetical disabilities wrote Arabic digits after they had heard them as number words. Planning time before writing each digit was registered. Analyses revealed that the two groups differed not only in arithmetical abilities but also in verbal and reading abilities. Children with arithmetical disabilities were overall slower in planning Arabic digits than were control children with normal arithmetical abilities. In addition, they showed a number size effect for numbers smaller than 10, suggesting a semantically mediated route in number processing. Control children did not need more planning time for large numbers (e.g., 8) than for small numbers (e.g., 3), suggesting a direct nonsemantic route. For both two- and three-digit numbers, both groups of children showed a number size effect, although the effect was smaller each time for control children. The presence of the stronger number size effect for children with arithmetical disabilities was seen as a delay in the development of quick and direct transcoding. The relation between transcoding problems and arithmetical disabilities is discussed. A defect in the linking of numerical symbols to analog numerical representations is proposed as an explanation for the transcoding problems found in some children. 相似文献
754.
L. van Domburgh R. Loeber D. Bezemer R. Stallings M. Stouthamer-Loeber 《Journal of abnormal child psychology》2009,37(7):967-980
Childhood predictors of adolescent offending careers were studied in 310 boys from the longitudinal Pittsburgh Youth Study
who started offending prior to age 12. Three main groups were distinguished: serious persisters (n = 95), moderately serious persisters (n = 117), desisters (n = 63), and an intermittent group (n = 35). Group membership was predicted using risk and promotive factors measured in childhood. Serious and moderately serious
persisters could be distinguished well from desisters (29.2% and 32.3% explained variance). Distinction between the two persister
groups proved somewhat more difficult (20.9% explained variance). More serious persisters than desisters showed disruptive
behavior, while moderately serious persisters fell in between. Further, more moderately serious persisters were marked by
social disadvantage. Family involvement, small family and positive peer relationships were promotive of desistance. Concluding,
early onset offenders show considerable heterogeneity in their adolescent offending careers which seem to some extent to be
predicted by different sets of risk and promotive factors. 相似文献
755.
Marjolein Luman Steffen J. P. van Noesel Alky Papanikolau Janneke Van Oostenbruggen-Scheffer Diane Veugelers Joseph A. Sergeant Jaap Oosterlaan 《Journal of abnormal child psychology》2009,37(8):1123-1135
This study compared children with ADHD-only, ADHD+ODD and normal controls (age 8–12) on three key neurocognitive functions:
response inhibition, reinforcement sensitivity, and temporal information processing. The goal was twofold: (a) to investigate
neurocognitive impairments in children with ADHD-only and children with ADHD+ODD, and (b) to test whether ADHD+ODD is a more
severe from of ADHD in terms of neurocognitive performance. In Experiment 1, inhibition abilities were measured using the
Stop Task. In Experiment 2, reinforcement sensitivity and temporal information processing abilities were measured using a
Timing Task with both a reward and penalty condition. Compared to controls, children with ADHD-only demonstrated impaired
inhibitory control, showed more time underestimations, and showed performance deterioration in the face of reward and penalty.
Children with ADHD+ODD performed in-between children with ADHD-only and controls in terms of inhibitory controls and the tendency
to underestimate time, but were more impaired than controls and children with ADHD-only in terms of timing variability. In
the face of reward and penalty children with ADHD+ODD improved their performance compared to a neutral condition, in contrast
to children with ADHD-only. In the face of reward, the performance improvement in the ADHD+ODD group was disproportionally
larger than that of controls. Taken together the findings suggest that, in terms of neurocognitive functioning, comorbid ADHD+ODD
is a substantial different entity than ADHD-only. 相似文献
756.
The primary aim of this paper is to analyze the concept of degrees of causal contribution for actual events and examine the
way in which it can be formally defined. This should go some way to filling out a gap in the legal and philosophical literature
on causation. By adopting the conception of a cause as a necessary element of a sufficient set (the so-called NESS test) we
show that the concept of degrees of causation can be given clear and even empirical meaning. We then apply a game theoretical
framework to derive a measure of causal contribution. Our favoured measure turns out to be a generalised version of the normalized
Penrose–Banzhaf index of voting power. 相似文献
757.
Judi Mesman Marinus H. van IJzendoorn Marian J. Bakermans-Kranenburg 《Developmental Review》2009,29(2):120-162
The Still-Face Paradigm (SFP) designed by Tronick, Als, Adamson, Wise, and Brazelton (Tronick, E., Als, H., Adamson, L., Wise, S., & Brazelton, T. B. (1978). Infants response to entrapment between contradictory messages in face-to-face interaction. Journal of the American Academy of Child and Adolescent Psychiatry, 17, 1–13) has been used for many different purposes in over 80 empirical studies. In the current paper, the nature and correlates of infant behavior in the SFP were examined in a systematic narrative review and a series of meta-analyses. The results of the meta-analyses confirmed the classic still-face effect of reduced positive affect and gaze, and increased negative affect, as well as a partial carry-over effect into the reunion episode consisting of lower positive and higher negative affect compared to baseline. The still-face effect is very robust as it was found regardless of most sample variations such as infant gender and risk status, and regardless of most procedural variations, such as the length of the SFP episodes and the use of intervals between episodes. The few moderator effects that were found in the meta-analyses tended to put findings from the narrative review in a new perspective. Additional meta-analyses confirmed the narrative review in finding that higher maternal sensitivity predicted more infant positive affect during the still-face. Infants’ higher positive affect and lower negative affect during the still-face were predictive of secure attachment at age 1 year. The meta-analytic results for maternal depression were equivocal. Implications for future research include a need for studies testing the role of the adults’ identity (parent versus stranger, mother versus father) to elucidate the relationship-specificity of the still-face effect. Also, the role of maternal sensitivity and temperament as potential moderators of the still-face effect need to be examined further. On a procedural level, the effects of the timing of the still-face and of the duration of the reunion on infant responses deserve future research attention. 相似文献
758.
Motor disorders are a frequent consequence of acquired brain injury (ABI) in children and much effort is currently invested in alleviating these deficits. The aim of the present study was to test motor imagery (MI) capabilities in children with ABI (n=25) and an age- and gender-matched control group (n=25). A computerized Virtual Radial Fitts Task (VRFT) was used to investigate the speed-accuracy trade-offs (or Fitts' law) that occur as target size is varied for both executed and imagined performance. In the control group, the speed for accuracy trade-off for both executed and imagined performance conformed to Fitts' law. In the ABI group, only executed movements conformed to Fitts' law. These findings suggest that children with ABI show an inferior ability to imagine the time needed to complete goal-directed movements with differential difficulty levels. 相似文献
759.
Ashley A. Gorman Jessica M. Foley Mark L. Ettenhofer Charles H. Hinkin Wilfred G. van Gorp 《Neuropsychology review》2009,19(2):186-203
This review focuses on the “real world” implications of infection with HIV/AIDS from a neuropsychological perspective. Relevant
literature is reviewed which examines the relationships between HIV-associated neuropsychological impairment and employment,
driving, medication adherence, mood, fatigue, and interpersonal functioning. Specifically, the relative contributions of medical,
cognitive, psychosocial, and psychiatric issues on whether someone with HIV/AIDS will be able to return to work, adhere to
a complicated medication regimen, or safely drive a vehicle will be discussed. Methodological issues that arise in the context
of measuring medication adherence or driving capacity are also explored. Finally, the impact of HIV/AIDS on mood state, fatigue,
and interpersonal relationships are addressed, with particular emphasis on how these variables interact with cognition and
independent functioning. The purpose of this review is to integrate neuropsychological findings with their real world correlates
of functional behavior in the HIV/AIDS population. 相似文献
760.
Imagining the Future of Photoacoustic Mammography 总被引:1,自引:0,他引:1
van der Burg S 《Science and engineering ethics》2009,15(1):97-110
How can a realistic ethical imagination about the future of a technology take shape? This article contains a reflection which is based on the experiences of an embedded ethicist in the context of biophysical research conducive to the development of photoacoustic mammography, which is intended for the non-invasive detection of breast cancer. Imagination in this context already informs the activities of the biophysical researchers, but its role is limited: biophysical future scenarios concentrate on the technological advances that photoacoustics could bring about. In this article it is argued that it is advisable to also consider the medical practice and the ways in which this practice is likely to change as an effect of the introduction of photoacoustic mammography into it. On the basis of this more encompassing imaginative endeavor it is possible to get a clearer idea about how new technologies are able to contribute to human well being, which is informative for the setting of research-goals/priorities and a responsible implementation of new technologies into the world. 相似文献