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221.
Michael C. Frank Sharon Goldwater Thomas L. Griffiths Joshua B. Tenenbaum 《Cognition》2010,117(2):107-125
The ability to discover groupings in continuous stimuli on the basis of distributional information is present across species and across perceptual modalities. We investigate the nature of the computations underlying this ability using statistical word segmentation experiments in which we vary the length of sentences, the amount of exposure, and the number of words in the languages being learned. Although the results are intuitive from the perspective of a language learner (longer sentences, less training, and a larger language all make learning more difficult), standard computational proposals fail to capture several of these results. We describe how probabilistic models of segmentation can be modified to take into account some notion of memory or resource limitations in order to provide a closer match to human performance. 相似文献
222.
In this comparative intervention study, 107 working individuals with above average levels of distress were randomly assigned to one of three conditions: acceptance and commitment therapy (ACT; n = 37); stress inoculation training (SIT; n = 37); or a waitlist control group (n = 33). The interventions were delivered to small groups in the workplace via two half-day training sessions. ACT and SIT were found to be equally effective in reducing psychological distress across a three month assessment period. Mediation analysis indicated that the beneficial impact of ACT on mental health resulted from an increase in psychological flexibility rather than from a change in dysfunctional cognitive content. Contrary to hypothesis, a reduction in dysfunctional cognitions did not mediate change in the SIT condition. Results suggest that the worksite may offer a useful, yet underutilised, arena for testing cognitive-behavioural theories of change. 相似文献
223.
Fransje Smits Stijn Ruiter Frank Van Tubergen 《Journal for the scientific study of religion》2010,49(2):247-263
This study examines the religious participation of Islamic immigrants in Belgium using data from the Migration History and Social Mobility Survey collected in 1994–1996 from 2,200 men who had immigrated from Turkey and Morocco. Religious participation is measured as mosque attendance, fasting during Ramadan, and sacrificing a sheep at the Festival of Sacrifice. Results show that the religious participation of Islamic immigrants depends on both premigration and postmigration characteristics. Religious participation is higher among immigrants who: (1) attended a Koranic school in their country of origin, (2) were socialized in a religious region of their home country, (3) received little schooling, (4) currently live in an area of Belgium with a greater number of mosques, and (5) associate with a high number of co‐ethnics. These results suggest that the religious participation of Islamic immigrants in Belgium is an outcome of characteristics unique to immigrants as well as processes common among the general population. 相似文献
224.
225.
André M. van der Laan René Veenstra Stefan Bogaerts Frank C. Verhulst Johan Ormel 《Journal of abnormal child psychology》2010,38(3):339-351
This study uses a social-ecological approach to the development of delinquency. The authors emphasize that a balance between
eliminating risk and enhancing protection across domains is essential in reducing problems and promoting competence. The cumulative
risk and promotive effects of temperament, family and school factors in preadolescence were examined on different groups of
delinquents (based on self-report) in early adolescence. Data from the first two waves of the TRAILS study (N = 2,230) were used. The results provide evidence for a compensatory model that assumes main effects of risk and promotive
factors on problem behavior. Accumulation of risks in preadolescence promoted being a serious delinquent in early adolescence,
with the strongest effects for temperament. Accumulation of promotive effects decreased being a delinquent and supported being
a non-delinquent. Furthermore, evidence is found for a counter-balancing effect of cumulative promotive and risk factors.
Exposure to more promotive domains in the relative absence of risk domains decreased the percentage of serious delinquents.
Our results did not support a protective model. Implications for prevention and intervention are discussed. 相似文献
226.
In high-stakes testing, often multiple test forms are used and a common time limit is enforced. Test fairness requires that ability estimates must not depend on the administration of a specific test form. Such a requirement may be violated if speededness differs between test forms. The impact of not taking speed sensitivity into account on the comparability of test forms regarding speededness and ability estimation was investigated. The lognormal measurement model for response times by van der Linden was compared with its extension by Klein Entink, van der Linden, and Fox, which includes a speed sensitivity parameter. An empirical data example was used to show that the extended model can fit the data better than the model without speed sensitivity parameters. A simulation was conducted, which showed that test forms with different average speed sensitivity yielded substantial different ability estimates for slow test takers, especially for test takers with high ability. Therefore, the use of the extended lognormal model for response times is recommended for the calibration of item pools in high-stakes testing situations. Limitations to the proposed approach and further research questions are discussed. 相似文献
227.
ABSTRACTAn analysis of the transition from railways to highways as the dominant British transport system during the twentieth century shows that public storylines about competing niche and regime technologies can have a powerful influence on socio-technical transitions. These storylines are developed by supporters and opponents of the competing technologies, with each group attempting to frame their favoured technology positively. The public salience of these storylines can be evaluated by assessing how highly they score on four elements of frame resonance: empirical fit, experiential commensurability, actor credibility, and macro-cultural resonance. These storylines can be seen at play across the entirety of the transition to a road-based transport system, from the very early history of the automobile through to the turn of the millennium, when public opposition to road transport was becoming increasingly pronounced. This case study uniquely traces discursive conflict over the entire course of a multi-decade transition. While existing literature in the multi-level perspective typically emphasises the disadvantages faced by niche-innovations, this case study shows that powerful storylines, enabled by the right cultural repertoires and possibly negative storylines about existing socio-technical systems, can create powerful political support for a new technology, giving it an advantage against more established incumbents. 相似文献
228.
We study the coalescence of neighbouring voids along close-packed directions in recent computer simulation studies of void-lattice formation. The stability against coalescence of a developing void lattice is found to depend very much on the detailed geometry of the local void distribution. The possibility of void coalescence as an artifact, caused by the incorrect assumption of homogeneous void nucleation in these simulations, is suggested and discussed. 相似文献
229.
Frank L. Schmidt Huy Le In‐Sue Oh 《International Journal of Selection & Assessment》2013,21(4):339-354
Relations between constructs are estimated based on correlations between measures of constructs corrected for measurement error. This process assumes that the true scores on the measure are linearly related to construct scores, an assumption that may not hold. We examined the extent to which differences in distribution shape reduce the correlation between true scores on a measure and scores on the underlying construct they are intended to measure. We found, via a series of Monte Carlo simulations, that when the actual construct distribution is normal, nonnormal distributions of true scores caused this correlation to drop by an average of only .02 across 15 conditions. When both construct and true score distributions assumed different combinations of nonnormal distributions, the average correlation was reduced by .05 across 375 conditions. We conclude that theory‐based scales intended to measure constructs usually correlate highly with the constructs they are constructed to measure. We show that, as a result, in most cases true score correlations only modestly underestimate correlations between different constructs. However, in cases in which the two constructs are redundant, this underestimation can lead to the false conclusion that the constructs are ‘correlated but distinct constructs,’ resulting in construct proliferation. 相似文献
230.
Daniel J. O’Rourke Ronald E. Smith Frank L. Smoll Sean P. Cumming 《Journal of Applied Sport Psychology》2013,25(4):398-412
We assessed the role of parental behaviors on sport performance anxiety. Measures of trait anxiety, parental pressure, and parent-initiated motivational climate were administered to youth swimmers throughout the season. High parental pressure within either a low mastery or a high ego motivational climate was associated with the highest levels of anxiety at all time points. An early-season, high-pressure/low-mastery combination was also associated with relative increases in anxiety over the season, whereas high pressure within a high mastery climate was associated with relative decreases. Results indicate that parental pressure can have differential effects depending upon motivational climate. 相似文献