公开市场操作公告对中国股市交易行为的影响

基于MRR结构模型,利用广义矩估计方法,从信息不对称和流动性成本角度考察了央行公开市场操作公告对股票市场交易行为的影响。实证结果表明,公开市场操作披露前股票市场的信息不对称程度、流动性成本并未发生显著变化,公开市场操作披露后30分钟内,信息不对称程度增加,流动性成本下降。在考虑了公开市场操作未预期的利率变化具体内容后,所得结果并没有显著变化。     

计算中国男性人体环节体积的二元回归方程的研究

采用CT—图像分析法,在尸体研究的基础上,对50例中国男性样本(18～23岁)进行了全身CT横断层扫描、影像分析和测算,获得了样本各环节的长度和体积等惯性数据。进而确定了中国男性青年人体体积的分布,并据此建立了以身高、体重为自变量的直接计算中国青年人体各环节体积的二元回归方程。     

多元线性回归方程及其应用

通过建立多元线性回归的数学模型,利用最小二乘估计得到正规方程组并进行相关性检验,从而解决相关实际问题。     

Physiologically Based Liver Modeling and Risk Assessment

Because of the inherent complexity of biological systems, there is often a choice between a number of apparently equally applicable physiologically based models to describe uptake and metabolism processes in toxicology or risk assessment. These models may fit the particular data sets of interest equally well, but may give quite different parameter estimates or predictions under different (extrapolated) conditions. Such competing models can be discriminated by a number of methods, including potential refutation by means of strategic experiments, and their ability to suitably incorporate all relevant physiological processes. For illustration, three currently used models for steady-state hepatic elimination--the venous equilibration model, the parallel tube model, and the distributed sinusoidal perfusion model--are reviewed and compared with particular reference to their application in the area of risk assessment. The ability of each of the models to describe and incorporate such physiological processes as protein binding, precursor-metabolite relations and hepatic zones of elimination, capillary recruitment, capillary heterogeneity, and intrahepatic shunting is discussed. Differences between the models in hepatic parameter estimation, extrapolation to different conditions, and interspecies scaling are discussed, and criteria for choosing one model over the others are presented. In this case, the distributed model provides the most general framework for describing physiological processes taking place in the liver, and has so far not been experimentally refuted, as have the other two models. These simpler models may, however, provide useful bounds on parameter estimates and on extrapolations and risk assessments.     

语气词在俄语口语中的结构功能

俄语传统语法历来认为语气词不充当句子成分,不发挥任何句法作用.然而,这种特性在口语中却发生了变化;有为数不少的语气词具有结构功能,在交际中发挥着极为重要的作用,这点在语气词研究中往往被忽视.受口语超语言特征的影响,语气词可以充当固定句位句素构成各种结构模式,表达各种情态意义.语气词发挥的结构功能主要有三大类:充当独立语句功能、充当语句结构要素功能及构成对话重复语句功能.     

关于广义Ramanujan-Nagell方程解数

设p是奇素数，D是适合p D是正奇数，证明了，当D≠Ap^r-1，其中r是正整数时，方程x^2 D=4p^n至多有1组正整数解（x,n）。     

诗意的批判--论萧红小说的反讽叙事

反讽叙事在萧红的小说中是进行国民性批判的主要叙事策略,这种对反讽的自觉运用使作者以一种更具审美性的方式含蓄而诗意地表现国民性批判的意图,同时也是萧红小说语言诗化特点形成的原因之一。反讽机制的运用使萧红的小说叙事实现了对现实世界和人性世界的深层揭示和哲学反思。     

正烯烃沸点与其分子结构之间定量关系的研究

本文根据分子结构的特点，借助图论探讨了正烯烃的沸点与分子结构的关系，提出了一个具有一定结构基础的定量关系。对４０种正烯烃的计算结果表明，沸点计算值都接近实验值，平均误差仅０．０５４％。     

Bayesian analysis of directed graphs data with applications to social networks

Summary.  A fully Bayesian analysis of directed graphs, with particular emphasis on applica- tions in social networks, is explored. The model is capable of incorporating the effects of covariates, within and between block ties and multiple responses. Inference is straightforward by using software that is based on Markov chain Monte Carlo methods. Examples are provided which highlight the variety of data sets that can be entertained and the ease with which they can be analysed.     

New imperfect rankings models for ranked set sampling

Ranked set sampling is a sampling approach that leads to improved statistical inference in situations where the units to be sampled can be ranked relative to each other prior to formal measurement. This ranking may be done either by subjective judgment or according to an auxiliary variable, and it need not be completely accurate. In fact, results in the literature have shown that no matter how poor the quality of the ranking, procedures based on ranked set sampling tend to be at least as efficient as procedures based on simple random sampling. However, efforts to quantify the gains in efficiency for ranked set sampling procedures have been hampered by a shortage of available models for imperfect rankings. In this paper, we introduce a new class of models for imperfect rankings, and we provide a rigorous proof that essentially any reasonable model for imperfect rankings is a limit of models in this class. We then describe a specific, easily applied method for selecting an appropriate imperfect rankings model from the class.