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991.
Theresa M. Marteau Marie Johnston Jane Kidd Susan Michie Rachel Cook Joan Slack 《Psychology & health》2013,28(1-2):13-22
Abstract The purpose of the current study was to determine which psychological models are most useful in predicting uptake of a prenatal screening test, maternal-serum alphafetoprotein screening for spina bifida and Down's syndrome. 1000 women eligible for the test completed standardised self-report questionnaires at two routine clinic visits to an antenatal clinic prior to the time when the test could take place. 902 underwent the screening test; 51 declined the test; and 47 did not undergo the test, giving no reason for this to staff. Knowledge of the test, the subjective expected utility attached to the test, and attitudes to doctors and medicine were all significant predictors of uptake behaviour. Results of a discriminant function analysis demonstrated distinct psychological processes underlying each of these three uptake behaviours, explaining 21% of the variance in uptake of screening. If uptake of screening is examined not as a dichotomous variable but as a group of behaviours, predictive models are identified accordingly. This would lead to rnodels of health-related behaviours as a heterogeneous rather than homogeneous phenomena, predicted and influenced by different causes. 相似文献
992.
Continuous performance tests (CPTs) are widely used in the assessment and study of attention deficit hyperactivity disorder (ADHD). Although CPTs have reliably found differences between children with ADHD and normal controls, discriminating between children with ADHD and children with subclinical levels of behavioral or cognitive problems is a more clinically relevant and difficult endeavor. Additionally, most studies use convenience samples from clinical care settings that may not represent the ADHD population as a whole. The current study assessed the utility of a clinically used CPT, the Test of Variables of Attention (TOVA), in distinguishing between children with ADHD and children with subclinical levels of attention/behavior problems. Participants constituted a representative sample of elementary school students at high risk for ADHD, including 116 children with ADHD and 51 subclinical controls. Results found no significant differences between the ADHD and subclinical group on CPT variables, and CPT performance did not reliably predict group membership. Implications of the findings are discussed. 相似文献
993.
A new bulk glassy alloy (BGA) showing macroscopic tensile plastic elongation at room temperature has been developed in the hypoeutectic Zr–Ni–Cu–Al alloy system. The hypoeutectic Zr–Ni–Cu–Al BGA shows a high Poisson's ratio, a low Young's modulus, and is highly malleable in compression. It exhibits a Poisson's ratio of 0.39, a Young's modulus of 73 GPa, and a distinct tensile plastic elongation of about 1.7% at room temperature with necking due to the operation of many shear bands. The tensile plastic deformability seems to originate from modifications of the glass structure with increasing the number of Zr–Zr atomic pairs in the hypoeutectic composition. 相似文献
994.
The behaviour of vacancies during isothermal ageing following quenching of an Al-1.7at.% Mg-1.1at.% Cu alloy has been studied by positron annihilation lifetime spectroscopy. The positron lifetime parameters vary in parallel with the Vickers hardness of the alloy, suggesting simultaneous migration of vacancies and changes in the size and concentration of vacancies containing clusters and dislocation loops. The results also explain the long hardness plateau observed previously in ageing experiments carried out between 100 and 240°C in terms of a continuous growth of Mg-Cu-vacancy clusters during ageing. The vacancy concentration of the clusters increases gradually until the setting in of the cluster Guinier-Preston-Bagaryatsky zone transformation. 相似文献
995.
Ekhard K.H. Salje Daniel Enrique Soto-Parra Antoni Planes Eduard Vives Marius Reinecker Wilfried Schranz 《Philosophical Magazine Letters》2013,93(8):554-560
The failure mechanism of porous materials under uniaxial stress has been investigated experimentally. Microporous SiO2, Vycor, has been subjected to slowly increasing compressive uniaxial stress with stress rates between 0.2 and 12.2?kPa/s. With increasing stress the strain changes stepwise with acoustic emission correlated with each volume collapse. The acoustic emission followed the characteristics of ‘crackling noise’ with a power law distribution over an exceptionally large interval of 6 decades at the slowest stress rate. The power law exponent is ?1.39. Possible applications in mining industry and others are discussed. 相似文献
996.
Elizabeth J. Marsh Jeffrey P. Lozito Sharda Umanath Elizabeth L. Bjork Robert A. Bjork 《Memory (Hove, England)》2013,21(6):645-653
A key educational challenge is how to correct students’ errors and misconceptions so that they do not persist. Simply labelling an answer as correct or incorrect on a short-answer test (verification feedback) does not improve performance on later tests; error correction requires receiving answer feedback. We explored the generality of this conclusion and whether the effectiveness of verification feedback depends on the type of test with which it is paired. We argue that, unlike for short-answer tests, learning whether one's multiple-choice selection is correct or incorrect should help participants narrow down the possible answers and identify specific lures as false. To test this proposition we asked participants to answer a series of general knowledge multiple-choice questions. They received no feedback, answer feedback, or verification feedback, and then took a short-answer test immediately and two days later. Verification feedback was just as effective as answer feedback for maintaining correct answers. Importantly, verification feedback allowed learners to correct more of their errors than did no feedback, although it was not as effective as answer feedback. Overall, verification feedback conveyed information to the learner, which has both practical and theoretical implications. 相似文献
997.
本文由张华华教授讲座内容整理而成,主要是关于计算机化考试的理论、技术、方法,以及美国教育进展评估给中国教育评估带来的启示.本文对于较全面深入了解计算机考试相关内容的读者具有重要借鉴意义. 相似文献
998.
The pseudodiagnosticity task has been used as an example of the tendency on the part of participants to incorrectly assess Bayesian constraints in assessing data, and as a failure to consider alternative hypotheses in a probabilistic inference task. In the task, participants are given one value, the anchor value, corresponding to P(D1|H) and may choose one other value, either P(D1|¬!H), P(D2|H), or P(D2|not;!H). Most participants select P(D2|H), or P(D2|¬!H) which have been considered inappropriate (and called pseudodiagnostic) because only P(D1|¬!H) allows use of Bayes' theorem. We present a new analysis based on probability intervals and show that selection of either P(D2|H), or P(D2|¬!H) is in fact pseudodiagnostic, whereas choice of P(D1|¬!H) is diagnostic. Our analysis shows that choice of the pseudodiagnostic values actually increases uncertainty regarding the posterior probability of H, supporting the original interpretation of the experimental findings on the pseudodiagnosticity task. The argument illuminates the general proposition that evolutionarily adaptive heuristics for Bayesian inference can be misled in some task situations. 相似文献
999.
Lesley J. Tranter 《Neuropsychology, development, and cognition. Section B, Aging, neuropsychology and cognition》2013,20(2):184-207
ABSTRACT The disuse hypothesis of cognitive aging attributes decrements in fluid intelligence in older adults to reduced cognitively stimulating activity. This study experimentally tested the hypothesis that a period of increased mentally stimulating activities thus would enhance older adults' fluid intelligence performance. Participants (N?=?44, mean age 67.82) were administered pre- and post-test measures, including the fluid intelligence measure, Cattell's Culture Fair (CCF) test. Experimental participants engaged in diverse, novel, mentally stimulating activities for 10–12 weeks and were compared to a control condition. Results supported the hypothesis; the experimental group showed greater pre- to post-CCF gain than did controls (effect size d?=?0.56), with a similar gain on a spatial-perceptual task (WAIS-R Blocks). Even brief periods of increased cognitive stimulation can improve older adults' problem solving and flexible thinking. 相似文献
1000.
This study investigated the degree of factorial invariance of the 30-item Rahim Emotional Quotient Index (REQI) (Afzalur Rahim et al., 2002) across gender and language, using multiple group confirmatory factor analysis. Respondents were 341 full-time employed applicants to programmes in a South African Business School (females = 39.6%, African language group = 60.1%; non-African/Western language group = 39.9). With regard to age, the majority of the sample (25.5%) fell into the category 31–35 years. The Satorra-Bentler scaled chi-square difference tests showed no statistically significant differences between different gender and language groups, with regard to factor structure, factor loadings, variances and covariance. The findings support the original five-factor structure of the REQI for the two language groups, as well as the two gender groups. 相似文献