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101.
经典的绘画作品感染并打动观众,是通过视觉这一感官体验来完成的。因此,在今天展览越来越多、展厅越来越大的情况下,有一些人从简单的视觉体验出发,使“视觉冲击力”这一曾经只运用于设计领域的词汇,在绘画中泛滥,进而波及工笔画领域。文章根据中国传统工笔画的品评标准,结合现代工笔画的绘画创作实践,分析视觉冲击力与经典的工笔画之间的矛盾与联系:经典的工笔画具有一定的视觉冲击,但是具有“视觉冲击力”的工笔画不一定就是经典的画作,真正的经典作品必须具有崇高的审美本质,在经过岁月的检验后,才能焕发出像珍珠一样夺目的光彩。  相似文献   
102.
今文《尚书》之《尧典》叙述尧观象授时、举贤任能、巡狩四方等事迹,树立了高大光辉的明君形象。从其材料来源、思想观念、语言形式及战国典籍的征引等多方面来看,《尧典》应编成于春秋时期。其编者应是孔子,春秋时代官学下移、私学兴起,讲史之风盛行,孔门以讲史教学,故孔子有编辑旧史佚闻之举。从文体方面来看,《尧典》以人物为中心,以事件为骨干,与《商书》、《周书》誓、命、训、诰诸体差别较大,具备了“传记”的诸种因素。  相似文献   
103.
随着两岸关系和平发展的持续推进,这项战略已经产生了强大的溢出效应。影响所及,两岸关系结构、台湾民众对两岸关系的认知结构以及台湾岛内话语结构等都发生了根本性变化,这种局面对岛内政党政治的基本生态和未来发展趋势产生了较大影响,两个主要政党都针对环境的变化进行了一定的调整,以求适应台海局势的结构性变化,谋求未来更多的发展空间。  相似文献   
104.
A simulation study of the binomial-logit model with correlated random effects is carried out based on the generalized linear mixed model (GLMM) methodology. Simulated data with various numbers of regression parameters and different values of the variance component are considered. The performance of approximate maximum likelihood (ML) and residual maximum likelihood (REML) estimators is evaluated. For a range of true parameter values, we report the average biases of estimators, the standard error of the average bias and the standard error of estimates over the simulations. In general, in terms of bias, the two methods do not show significant differences in estimating regression parameters. The REML estimation method is slightly better in reducing the bias of variance component estimates.  相似文献   
105.
In this work, we discuss the class of bilinear GARCH (BL-GARCH) models that are capable of capturing simultaneously two key properties of non-linear time series: volatility clustering and leverage effects. It has often been observed that the marginal distributions of such time series have heavy tails; thus we examine the BL-GARCH model in a general setting under some non-normal distributions. We investigate some probabilistic properties of this model and we conduct a Monte Carlo experiment to evaluate the small-sample performance of the maximum likelihood estimation (MLE) methodology for various models. Finally, within-sample estimation properties were studied using S&P 500 daily returns, when the features of interest manifest as volatility clustering and leverage effects. The main results suggest that the Student-t BL-GARCH seems highly appropriate to describe the S&P 500 daily returns.  相似文献   
106.
In analyzing data from unreplicated factorial designs, the half-normal probability plot is commonly used to screen for the ‘vital few’ effects. Recently, many formal methods have been proposed to overcome the subjectivity of this plot. Lawson (1998) (hereafter denoted as LGB) suggested a hybrid method based on the half-normal probability plot, which is a blend of Lenth (1989) and Loh (1992) method. The method consists of fitting a simple least squares line to the inliers, which are determined by the Lenth method. The effects exceeding the prediction limits based on the fitted line are candidates for the vital few effects. To improve the accuracy of partitioning the effects into inliers and outliers, we propose a modified LGB method (hereafter denoted as the Mod_LGB method), in which more outliers can be classified by using both the Carling’s modification of the box plot (Carling, 2000) and Lenth method. If no outlier exists or there is a wide range in the inliers as determined by the Lenth method, more outliers can be found by the Carling method. A simulation study is conducted in unreplicated 24 designs with the number of active effects ranging from 1 to 6 to compare the efficiency of the Lenth method, original LGB methods, and the proposed modified version of the LGB method.  相似文献   
107.
Despite the renewed interest in youth volunteering in recent years, there remain major gaps in our knowledge of its consequences. Drawing data from the National Longitudinal Study of Adolescent to Adult Health, we examine the long-term effects of youth volunteering on the civic and personal aspects of volunteers’ lives. Our results suggest that youth volunteering has a positive return on adult volunteering only when it is voluntary, and that net of contextual factors neither voluntary nor involuntary youth service has a significant effect on adult voting. Regarding personal outcomes, our findings indicate that the psychological benefits of youth volunteering accrue only to voluntary participants, whereas both voluntary and involuntary youth service are positively associated with educational attainment and earnings in young adulthood. Taken together, these results lend support to the case for youth volunteer programs, though the civic benefits of these programs appear to be less dramatic than generally suggested.  相似文献   
108.
Higher educated people tend to be more accepting of homosexuality than lower educated people. This has inspired claims that education leads to a higher acceptance of homosexuality. Alternatively, the association between education and acceptance of homosexuality could be confounded by (un)observed family background and stable individual characteristics. This study investigated the association between education and acceptance of homosexuality and the role of potential confounders in a unique longitudinal sample of British siblings. Multilevel and fixed effects analyses show that both perspectives apply. A large part of the association between education and acceptance of homosexuality could be attributed to family background and observed individual characteristics (one third), as well as unobserved individual characteristics (an additional third), but the positive association remains. Findings are discussed in light of existing explanations regarding the effect of education on the acceptance of homosexuality.  相似文献   
109.
Sample selection and attrition are inherent in a range of treatment evaluation problems such as the estimation of the returns to schooling or training. Conventional estimators tackling selection bias typically rely on restrictive functional form assumptions that are unlikely to hold in reality. This paper shows identification of average and quantile treatment effects in the presence of the double selection problem into (i) a selective subpopulation (e.g., working—selection on unobservables) and (ii) a binary treatment (e.g., training—selection on observables) based on weighting observations by the inverse of a nested propensity score that characterizes either selection probability. Weighting estimators based on parametric propensity score models are applied to female labor market data to estimate the returns to education.  相似文献   
110.
商业信用的资源再配置假说认为,商业信用可实现银行信贷资金的再配置,从而提高资源配置效率。以2004—2007年中国工业企业微观数据为基础,对我国商业信用的资源配置效应以及恶意拖欠基础上的强制性信用特征进行的检验结果表明,在我国,获取更多银行信贷的企业(包括国有企业)不仅未能提供更多商业信用,反而获取了更多商业信用,而市场势力的存在可能是导致这一配置结果的扭曲性因素;拥有更多应收账款的企业倾向于扩大应付账款规模,从而使企业间债务关系呈现出较强的"三角债"趋势。此外,与出口企业相比,产品内销企业在商业信用的供给中面临着更多的坏账损失风险。这说明我国商业信用的产生具有显著的恶意拖欠特征与违约风险。我国的商业信用不仅未能改善资源配置效率,反而增大了市场的交易费用和运行风险。  相似文献   
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