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91.
为了体现金融资产的长记忆性,采用次分数布朗运动刻画备兑权证标的资产价格变化的行为模式。利用随机分析理论和偏微分方程方法,建立了次分数布朗运动下带交易费用的备兑权证定价模型,进一步研究了定价模型的参数估计问题。最后,采用我国权证市场实际数据进行了实证分析,通过比较不同定价模型的结果说明了长记忆性和交易费用对定价结果有着显著的影响。  相似文献   
92.
The objective of this study is to extend previous research on total quality management (TQM)-context-performance relationships and ‘fit’ using multiple methods. We combine artificial neural networks (ANNs) with structural equation modelling (SEM) to analyse several hypotheses and propositions. This is the first study in this area of research that utilises ANNs and a triangulation technique in the presence of several contextual factors. The SEM analyses suggest that company size and industry type may have contingency effects on some of the TQM practices and/or TQM-performance relationships. However, the ANN models have shown that these two contingency factors do not moderate TQM outcomes, implying that all organisations can benefit from TQM regardless of size and type. As well, these models show that formal TQM implementation and/or ISO certifications do not add any predictive power to the ANN models except in one case: TQM implementation and/or ISO certification added to organisational effectiveness and customer results to predict financial and market (F&M) results. The results further indicate that even though implementing TQM alone has a bigger impact on F&M results than obtaining ISO certification alone, combining the two will have an even greater impact on these results. Joint implementation leads to greater improvements in organisational effectiveness, which, in turn, has a positive effect on customer results and consequently F&M results. This is a unique finding within the context of moderator effects on TQM-performance relationships.  相似文献   
93.
本文介绍了国内外主要企业财务危机预警模型,对模型的空间几何意义进行解释。提出了企业财务危机预警双基点距离比值模型,该模型采用非线性方法对危机企业与非危机企业的财务指标集合进行分割。用112例样本实证,预警识别率达到92.8%。  相似文献   
94.
In this paper, we consider the center location improvement problems under the sum-type and bottleneck-type Hamming distance. For the sum-type problem, we show that achieving an algorithm with a worst-case ratio of O(log |V|) is NP-hard, and for the bottleneck-type problem, we present a strongly polynomial algorithm.  相似文献   
95.
基于超越对数生产函数的随机前沿模型对2000-2017年中国水稻、小麦和玉米等三类粮食作物TFP进行测算,并在构建要素错配指数的基础上,对单位规模土地上投入的劳动、机械、化肥和种子等4种要素错配对粮食作物实际TFP增长率的影响进行时空差异分析。研究结果显示,2000-2017年粮食作物的实际TFP增长率平均为2.24%,有效TFP增长率约为0.73%;狭义技术进步对TFP增长的拉动作用在减弱,要素配置效率的优化对TFP的提升作用在增强;劳动投入过度比较突出,是引发粮食生产要素配置不优的主要原因;从空间区域来看,东部地区要素错配程度相对较低,西部地区相对较高;中部地区粮食作物的实际TFP增长率对要素错配的敏感度要强于东部和西部地区。  相似文献   
96.
In an event study, Hendricks and Singhal [Hendricks KB, Singhal VR. Quality awards and the market value of the firm: an empirical investigation. Management Sci 1996;42:415–36.] find evidence that firms that win quality awards are further rewarded with a stock price increase on the day of the award announcement. We revisit Hendricks and Singhal (1996), extend their research and find four reasons why management, owners and analysts should be cautious about expecting an abnormal return when a firm wins a quality award. First, in our sample of Baldrige Award winners, the evidence of a stock price response on the announcement day is only marginally significant. Second, in our sample of State quality award winners, the announcement day relationship between stock returns and winning awards is not significant. Third, in the most recent subperiod, 1992–1997, we find no evidence of positive abnormal returns. Fourth, the marginally significant Baldrige results are actually driven by just four companies. A company-by-company microanalysis reveals that only 50% of the award winners experienced positive abnormal returns. The diminishing stock price response on event day does not necessarily imply a lack of stockholder rewards. Evidence from other studies suggests that the stockholders are rewarded for successful total quality management (TQM) implementation, but the rewards can come long before and after the formal award is presented. From a shareholder value perspective, TQM still matters but the award ceremonies may not.  相似文献   
97.
基于Web的远程网络课件的设计与开发   总被引:3,自引:0,他引:3  
本文从分析网络课件的基本特性及基本的设计开发过程入手,以<现代交换原理>网络课件为案例,详细讨论了网络课件设计与开发过程中的关键问题,为网络课件的开发提供参考.  相似文献   
98.
用聚丙烯酰胺凝胶电泳方法分析竹亚科九属二十七种植物过氧化物酶和酯酶同工酶,结果表明:过氧化物酶同工酶谱在种间明显差异,各竹种有特征酶谱。其酶谱特征及酶谱距离可作为竹种分类特征之—,有助于竹种的分类,同时也可了解种间亲缘关系。而酯酶同工酶谱在种间差异小,不宜作竹种的分类特征,但也能反映出种间的亲缘关系。  相似文献   
99.
We compared the aquatic metazoan community structure in bamboo stumps between a lowland (Kosinggolan; 200 m a.s.l.) and a highland site (Moat; 1030–1050 m a.s.l.) in North Sulawesi. The lowland bamboo stumps harbored 38 taxa including 2 predators, and the highland stumps harbored 35 taxa including 2 predators. In total 45 taxa were recorded, including 3 predators. Dominant detritivores were Tipulidae, Scirtidae, Chironomidae, Culicidae and Ceratopogonidae. The sole dominant predators wereToxorhynchites mosquito larvae, which occurred in 67% and 28% of stumps at the lowland and the highland sites, respectively. Although the mean biomass per stump did not differ significantly between the sites, the mean number of species per stump was significantly smaller at the lowland site. In addition, the variation in species composition among stumps was greater at the lowland site than at the highland site. Among dominant taxonomic groups, the number of non-predatory culicid species per stump was smaller at the lowland site where their predator,Toxorhynchites, was more abundant, although both sites had the same number of culicid species. In the presence ofToxorhynchites, the density and biomass of other culicids per stump were reduced significantly. The difference in predator density might affect differences in the local-scale community structure of individual bamboo stumps.  相似文献   
100.
In this paper we consider semiparametric inference methods for the time scale parameters in general time scale models (Oakes, 1995, Duchesne and Lawless, 2000). We use the results of Robins and Tsiatis (1992) and Lin and Ying (1995) to derive a rank-based estimator that is more efficient and robust than the traditional minimum coefficient of variation (min CV) estimator of Kordonsky and Gerstbakh (1993) for many underlying models. Moreover, our estimator can readily handle censored samples, which is not the case with the min CV method.  相似文献   
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