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251.
Journal of Philosophical Logic - Kripke’s Fregean quantification logic FQ fails to formalize the usual first-order logic with identity due to the interpretation of the conditional operator.... 相似文献
252.
Drawing on Dewey's pragmatic perspective on talent cultivation and previous research on promoting employee creativity in industry, this study investigates student creativity performance in relation to teacher's encouragement, intrinsic motivation, and creative process engagement. Based on survey data collected from 140 vocational high school students who participated in a nation‐wide contest in Taiwan, path analyses were performed using structure equation modeling techniques. The results indicate that both teacher's encouragement and intrinsic motivation have a significant, although indirect, effect on student creativity, and that creative process engagement, as opposed to teacher encouragement or intrinsic motivation, has a direct and significant mediating effect on student creativity. This finding is in partial agreement with prior research which reports student creativity is positively associated with teacher encouragement and intrinsic motivation, highlighting the mediating role of creative process engagement in facilitating student creative performance. 相似文献
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The multilevel logistic regression model (M-logit) is the standard model for modeling multilevel data with binary outcomes. However, many assumptions and restrictions should be considered when applying this model for unbiased estimation. To overcome these limitations, we proposed a multilevel CART (M-CART) algorithm which combines the M-logit and single level CART (S-CART) within the framework of the expectation-maximization. Simulation results showed that the proposed M-CART provided substantial improvements on classification accuracy, sensitivity, and specific over the M-logit, S-CART, and single level logistic regression model when modeling multilevel data with binary outcomes. This benefit of using M-CART was consistently found across different conditions of sample size, intra-class correlation, and when relationships between predictors and outcomes were nonlinear and nonadditive. 相似文献
254.
H. Y. Wu Y. H. Chen P. F. Yin Z. R. Zhang X. Y. Han X. Y. Li 《Philosophical Magazine Letters》2019,99(1):29-38
The effects of pressure on the mechanical and dynamical stability of NaAlSi have been fully investigated by first-principles calculations within the generalised gradient approximation (GGA). The obtained results show that the optimised lattice constants, atomic positions and elastic constants at ambient pressure are in good agreement with the available experimental and theoretical data. The lattice constants decrease monotonically with increasing pressure. The elastic constant C11, C12, C13, C33 and C66 increase while C44 decreases with increasing pressure. It is found that NaAlSi is mechanically unstable when the pressure is above 25.97?GPa. The phonon-dispersion curves along several high symmetry lines are obtained. The phonon frequencies at the Z point decrease with increasing pressure and completely soften to zero at 27.52?GPa, further confirming the structural instability of NaAlSi. 相似文献
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Double‐discount is an effective format for promoting purchase decisions. However, extant literature has overlooked how temporal order of discounts applied affects consumers’ purchase decisions. In this paper, we show that the sequence of discount magnitude (e.g., 10% followed by 40% vs. 40% followed by 10%) leads to biases in consumer judgment and influences the perceived appeal and purchase intention of the deal. We term this the double‐discount sequence effect. Using four experiments, we showed that double‐discount in an ascending sequence (e.g., taking 10% off, then an additional 40% off) is preferable over that in a descending sequence. We also found that discount application sequence—but not the presentation order—matters to consumers. Consumers anchor on the first discount they encounter and evaluate the second discount with respect to this first one. 相似文献
259.
Anne Conway Wen-Jui Han Jeanne Brooks-Gunn Jane Waldfogel 《Journal of child and family studies》2017,26(8):2237-2251
Associations between first-year maternal employment and mother—and youth-reported externalizing behavior at age 15 were examined paying attention to potential mediating roles of home and child care environments by 36?months, effortful control at 54?months, and externalizing behavior at 54?months and middle childhood. We used data from the NICHD Study of Early Child Care and Youth Development (n?=?922 non-Hispanic White children) which is a prospective birth cohort study that followed children from birth to age 15. Full-time first-year maternal employment was associated with higher levels of externalizing behavior at age 15 through higher maternal depressive symptoms by 36?months, lower effortful control at 54?months, and higher externalizing behavior at 54?months and middle childhood. Part-time first-year maternal employment was not associated with higher externalizing behavior at age 15. 相似文献
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There is a long and interesting history in the study of the positive and negative effects of sacrifice, but few researchers have focused on how one’s marital partner being the recipient of sacrifice may lead to different outcomes. Based on conservation of resources theory, we suggested that a partner’s social support could be a potential moderator between sacrifice and well-being. To examine our hypothesis, we invited 141 Taiwanese couples to participate in our study. As expected, we found that only for those individuals whose partners provided less social support to them, the more they sacrificed, the lower marital satisfaction and the higher depressive symptoms they reported. In contrast, this effect was not found for the context in which a partner provided more social support. In addition, the negative correlation between a partner’s sacrifice and one’s depressive symptoms became stronger when an individual provided more support to their sacrificing partner. Our findings highlight that the relationship between sacrifice and well-being are contingent upon context, and are particularly dependent on whether the recipient of sacrifice can provide a supportive relationship. 相似文献