从《物色》测析昭明对刘勰的"深爱接之"

昭明太子萧统与刘勰的关系 ,是齐梁文学研究中的重要课题。二者一编纂《文选》,为出色选家 ;一巧雕“文心”,为大文论家 ,均对后代产生深远影响。直接记录二者关系的可靠史料 ,只有《梁书·刘勰传》一条 :“昭明太子好文学 ,深爱接之。”关于萧、刘二人以及《文选》和《文心雕龙》的关系 ,目前学界有五种意见。此文从另一新的角度——审美情趣的相通 ,探讨一下二者的关系 ,测析昭明太子为何对刘勰“深爱接之”。     

A class of weighted dependence measures for bivariate failure time data

This paper considers a class of summary measures of the dependence between a pair of failure time variables over a finite follow-up region. The class consists of measures that are weighted averages of local dependence measures, and includes the cross-ratio-measure and finite region version of Kendall's τ; recently proposed by the authors. Two new special cases are identified that can avoid the need to estimate the bivariate survivor function and that admit explicit variance estimators. Nonparametric estimators of such dependence measures are proposed and are shown to be consistent and asymptotically normal with variances that can be consistently estimated. Properties of selected estimators are evaluated in a simulation study, and the method is illustrated through an analysis of Australian Twin Study data.     

Designing and integrating composite networks for monitoring multivariate gaussian pollution fields

Networks of ambient monitoring stations are used to monitor environmental pollution fields such as those for acid rain and air pollution. Such stations provide regular measurements of pollutant concentrations. The networks are established for a variety of purposes at various times so often several stations measuring different subsets of pollutant concentrations can be found in compact geographical regions. The problem of statistically combining these disparate information sources into a single 'network' then arises. Capitalizing on the efficiencies so achieved can then lead to the secondary problem of extending this network. The subject of this paper is a set of 31 air pollution monitoring stations in southern Ontario. Each of these regularly measures a particular subset of ionic sulphate, sulphite, nitrite and ozone. However, this subset varies from station to station. For example only two stations measure all four. Some measure just one. We describe a Bayesian framework for integrating the measurements of these stations to yield a spatial predictive distribution for unmonitored sites and unmeasured concentrations at existing stations. Furthermore we show how this network can be extended by using an entropy maximization criterion. The methods assume that the multivariate response field being measured has a joint Gaussian distribution conditional on its mean and covariance function. A conjugate prior is used for these parameters, some of its hyperparameters being fitted empirically.     

Correlation in a Bayesian framework

The authors consider the correlation between two arbitrary functions of the data and a parameter when the parameter is regarded as a random variable with given prior distribution. They show how to compute such a correlation and use closed form expressions to assess the dependence between parameters and various classical or robust estimators thereof, as well as between p‐values and posterior probabilities of the null hypothesis in the one‐sided testing problem. Other applications involve the Dirichlet process and stationary Gaussian processes. Using this approach, the authors also derive a general nonparametric upper bound on Bayes risks.     

Differential equation models for statistical functions

Differential equations have been used in statistics to define functions such as probability densities. But the idea of using differential equation formulations of stochastic models has a much wider scope. The author gives several examples, including simultaneous estimation of a regression model and residual density, monotone smoothing, specification of a link function, differential equation models of data, and smoothing over complicated multidimensional domains. This paper aims to stimulate interest in this approach to functional estimation problems, rather than provide carefully worked out methods.     

以现代教学论指导普通物理教学

本文针对师范院校非物理专业的“普通物理”教与学的矛盾,以现代教学理论为指导,近年来探索新的教学策略,并致力实施,调动了学习积极性和改进评价,取得了较好效果。     

利用风险投资促进高校科技成果转化探讨

风险投资可以有效弥补高校科技成果转化中的资金缺口,也可提高高校科技企业后续融资能力。针对目前我国高校科技成果转化中风险投资参与度偏低的现状,文章在分析风险投资对促进高校科技成果的必要性基础上,研究了影响风险投资资金投资于高校科技成果的主要障碍因素,并提出了相应的对策。     

对信息不对称问题的重新思考

自阿克洛夫以来,经济理论界在研究信息不对称问题时,由于受传统刻画不确定性方法的束缚,没有认识到个人在做出决策时对其他参与者的类型集的主观估计的重要作用,因此缺乏对某些问题的现实解释力。对传统理论的假设做出合理的改变,才能拓展对信息不对称问题的研究途径,得出新的结论。     

对数正态分布参数的最大似然估计

利用最大似然估计法求出了对数正态分布两个参数的估计量,并讨论了它们的无偏性和相合性。