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221.
Cross‐situational word learning, like any statistical learning problem, involves tracking the regularities in the environment. However, the information that learners pick up from these regularities is dependent on their learning mechanism. This article investigates the role of one type of mechanism in statistical word learning: competition. Competitive mechanisms would allow learners to find the signal in noisy input and would help to explain the speed with which learners succeed in statistical learning tasks. Because cross‐situational word learning provides information at multiple scales—both within and across trials/situations—learners could implement competition at either or both of these scales. A series of four experiments demonstrate that cross‐situational learning involves competition at both levels of scale, and that these mechanisms interact to support rapid learning. The impact of both of these mechanisms is considered from the perspective of a process‐level understanding of cross‐situational learning. 相似文献
222.
HaiYing Wu YaHong Chen XinFang Su ChengRong Deng Zi-Jiang Liu 《Philosophical Magazine Letters》2013,93(4):198-204
A phase transition of MgS under high pressure is investigated using a first-principles method. It is found from energy-volume calculations that the rock-salt (B1) phase of MgS transforms into a FeSi-type (B28) phase at 143?GPa. The calculated ground-state parameters in the B1 phase are in excellent agreement with available experimental and theoretical data. Ab initio phonon calculations are also performed to investigate the structural behaviour of MgS under high pressure. An unstable transverse acoustic mode and a phase transition from B1 to B28 phase at ~143.7?GPa driven by this soft mode are predicted. The B28 structure of MgS is stable up to 350?GPa according to lattice dynamics calculations. 相似文献
223.
H. R. P. Inoue† M. Kitamura‡ C. M. Wayman and Haydn Chen 《Philosophical Magazine Letters》2013,93(6):345-353
Abstract Phase stability of the intermetallic compound Al3Nb is investigated as a function of nickel additions by band structure calculations based on an extended Hueckel tight-binding method. With this method, the electronic structure and total energies of the Al6-n -Ni n Nb2 compounds (where n is an integer from 0 to 6) are calculated for both D022 and L12 structures under the assumption that nickel substitutes for aluminium. The electronic total energies obtained from integration of the energy states of all electrons considered have shown that the D022 structure is stable in the binary Al3Nb compound as compared with the L12 structure; conversely, the L12 structure is stable for compounds with n values greater than 1. These calculations are in good agreement with X-ray diffraction results reported by Schubert and co-workers. Differences in the electronic total energy per atom between D022 and L12 are - 0·79 eV and 0·56 eV for n equal to 0 and 2, respectively. 相似文献
224.
Tae Wook Heo Yi Wang Saswata Bhattacharya Xin Sun Shenyang Hu Long-Qing Chen 《Philosophical Magazine Letters》2013,93(2):110-121
We propose a phase-field model for modeling microstructure evolution during deformation twinning. The order parameters are proportional to the shear strains defined in terms of twin plane orientations and twinning directions. Using a face-centered cubic Al as an example, the deformation energy as a function of shear strain is obtained using first-principle calculations. The gradient energy coefficients are fitted to the twin boundary energies along the twinning planes and to the dislocation core energies along the directions that are perpendicular to the twinning planes. The elastic strain energy of a twinned structure is included using the Khachaturyan's elastic theory. We simulated the twinning process and microstructure evolution under a number of fixed deformations and predicted the twinning plane orientations and microstructures. 相似文献
225.
Employing the implicit priming task, we examined whether Chinese words that shared the initial onset consonant could be typed, using the phonetic-based method (called zhuyin), with faster response times than words that did not share the initial onset consonant. We also examined the effect of sharing the initial tonal syllable. A significant onset preparation effect and a significant syllable preparation effect were both observed. The latter was found to vary linearly with the number of segments in the syllable. The slope of 63 ms was similar to the 70-ms onset effect, suggesting that the syllable effect was segment-based. The results contrasted with the lack of an onset effect previously reported for speaking, and were interpreted as supporting the output constraint hypothesis which states that the kind of outputs a production system is designed to produce (speaking vs. typing) can flexibly and adaptively alter the way the system is organized and operates. 相似文献
226.
Yuh‐shiow Lee Kuan‐Nan Chen 《British journal of psychology (London, England : 1953)》2013,104(1):119-129
This study investigated the influences of sentence surface forms on the misinformation effect. After viewing a film clip, participants received a post‐event narrative describing the events in the film. Critical sentences in the post‐event narrative, presented in either a statement or a question form, contained misinformation instead of questions with embedded false presuppositions; thus participants did not have to answer questions about the original event. During the final cued‐recall test, participants were informed that any relevant information presented in the post‐event narrative was not in the original event and that they should not report it. Consistent with previous findings, Experiment 1 demonstrated that post‐event information presented as an affirmative statement produced the misinformation effect. More importantly, post‐event information presented in a question form, regardless of whether it contained a misleading or studied item, increased the recall of correct information and reduced false recall. Experiment 2 replicated the main finding and ruled out an alternative explanation based on the salience of misleading items. Post‐event information presented in a question form created a condition similar to that which produces the testing effect. 相似文献
227.
Linda B. Smith Chen Yu Hanako Yoshida Caitlin M. Fausey 《Journal of cognition and development》2013,14(3):407-419
Head-mounted video cameras (with and without an eye camera to track gaze direction) are being increasingly used to study infants’ and young children's visual environments and provide new and often unexpected insights about the visual world from a child's point of view. The challenge in using head cameras is principally conceptual and concerns the match between what these cameras measure and the research question. Head cameras record the scene in front of faces and thus answer questions about those head-centered scenes. In this “Tools of the Trade” article, we consider the unique contributions provided by head-centered video, the limitations and open questions that remain for head-camera methods, and the practical issues of placing head cameras on infants and analyzing the generated video. 相似文献
228.
Artemis Chang Shu-Chen Chen Shu-Cheng Steve Chi 《European Journal of Work and Organizational Psychology》2013,22(6):859-874
This study examined the effects of role demand on both work–family conflict and family–work conflict, and the moderating effects of role salience and support on these relationships. Based on 391 dual-career (managerial and blue-collar employees) couples from a Taiwanese company in China, the results of this survey study showed clear gender differences in the patterns of relationships observed. For men, the most important demands that negatively impacted on work–family conflict were frequency of overtime and frequency of socializing for work purposes (yingchou), and supervisory support buffered the negative impact of frequent overtime. For women however, strong supervisory support and low work role salience were more important for reducing work–family conflict, and there was no significant main effect found for any of the role demand factors. Furthermore, women with high work role salience were more likely to feel the impact of yingchou on work–family conflict. In the family domain, the most influential demand for men was hours spent on household tasks, but for women, it was the frequency of family-related leave. Interestingly, males reported higher family role salience than females and spouse support intensified rather than buffered the positive impact of hours spent on household tasks on family–work conflict for males. 相似文献
229.
Yiwei Chen 《Neuropsychology, development, and cognition. Section B, Aging, neuropsychology and cognition》2013,20(1):58-67
The present study tested strategies to help older adults correct their context-induced biases. Two hundred and seventy-two young and older adults participated in this study. Participants read vignettes about two target persons, with true statements printed in black and false statements (either positive or negative trait information) printed in red. Participants in the no-strategy condition were asked to rate the target persons on the relevant trait scales immediately after reading the vignettes. Participants in the feedback condition took a traditional source memory test and received feedback of correct sources of true and false statements. For the participants in the next two conditions, accountability was induced either before or after they encoded information about the target persons. It was found that the feedback manipulation helped older adults correct their context-induced biases. In addition, accountability induced before encoding helped older adults reduce their context-induced biases, whereas accountability induced after encoding did not help. 相似文献
230.